How to Overhaul the Engine Controls - Removal & Installation Chevrolet Impala VIII

INTRODUCTION

This article covers removal, overhaul and installation procedures (when given by manufacturer). If component removal and installation is primarily an unbolt and bolt-on procedure, only a torque specification may be supplied.

Removal Procedure (3.1L)

1. Remove the left inner fender brace. Refer to «BRACE REPLACEMENT - FRONT FENDER UPPER DIAGONAL»(ref-176380-S37297811672005050400000) .
2. Remove the air cleaner intake duct. Refer to «AIR CLEANER INTAKE DUCT»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
3. Remove the 2 screws (2) from the air cleaner housing sections.
4. Remove the air cleaner cover assembly (1).
5. Without disconnecting the powertrain control module (PCM) connectors, remove the PCM and the harness from the air cleaner housing.
6. Remove the air cleaner housing (1) by pulling the cover from the 2 rubber grommets (2) in the engine compartment.
7. Inspect the air cleaner housing assembly for signs of damage and replace if necessary.

Scheme 1

1. Install the air cleaner housing by pushing the cover (1) into the 2 rubber grommets (2) in the engine compartment.
2. Install the PCM and the harness into the air cleaner housing (3).
3. Install the air cleaner housing cover assembly (1). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/impala/viii-1999-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the 2 screws (2) to the air cleaner housing. Tighten the screws to 3 N.m (27 lb in).
5. Install the air cleaner intake duct. Refer to «AIR CLEANER INTAKE DUCT»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
6. Install the left inner fender brace. Refer to «BRACE REPLACEMENT - FRONT FENDER UPPER DIAGON»(ref-176380-S37297811672005050400000) .

Scheme 2

1. Remove the air cleaner intake duct. Refer to «AIR CLEANER INTAKE DUCT»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
2. Remove the left inner fender brace (5).
3. Remove the 2 screws (6) that are holding the air cleaner element housing to the powertrain control module (PCM) housing.
4. Remove the air cleaner housing cover (1) from the air cleaner housing.
5. Without disconnecting the PCM connectors, remove the PCM (4) from the air cleaner housing (3).
6. Remove the air cleaner assembly by pulling the housing away from the rubber grommets in the engine compartment.

Scheme 3

1. Install the air cleaner assembly by pushing the housing into the rubber grommets in the engine compartment.
2. Install the PCM (4) into the air cleaner housing (3). NOTE: Refer to «FASTENER NOTICE»(/chevrolet/impala/viii-1999-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
3. Install the air cleaner housing cover (1) to the air cleaner housing (3).
4. Install the air cleaner housing cover screws (6). Tighten the screws to 4 N.m (35 lb in).
5. Install the inner fender brace (5).
6. Install the inner fender brace bolts. Tighten the bolts to 47 N.m (35 lb ft).
7. Install the air cleaner intake duct. Refer to «AIR CLEANER INTAKE DUCT»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .

1. Loosen the air cleaner intake duct clamps (2,6).
2. Remove the PCV tube from the air cleaner intake duct.
3. Disconnect the intake air temperature (IAT) sensor electrical connector (3).
4. Disconnect the mass air flow (MAF) sensor electrical connector (5).
5. Remove the air cleaner intake duct from the air cleaner assembly (8) and the throttle body.
6. Loosen the clamp on the MAF sensor and remove the air cleaner intake duct from the MAF sensor (7).
7. If replacing the air cleaner intake duct, remove the IAT sensor (1) with a twisting and pulling motion.

Installation Procedure

1. If removed, install the IAT sensor (1).
2. Install the air cleaner intake duct to the MAF sensor (7).
3. Install the air cleaner intake duct to the throttle body and the air cleaner assembly. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/impala/viii-1999-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
4. Install the air cleaner intake duct clamps (2,6). Tighten the clamps to 2 N.m (18 lb in).
5. Connect the MAF sensor electrical connector (5).
6. Connect the IAT sensor electrical connector (3).
7. Install the PCV tube (4) to the air cleaner intake duct.

Removal Procedure (3.8L)

1. Disconnect the intake air temperature (IAT) sensor electrical connector (3).
2. Remove the IAT sensor with a twisting and pulling motion.
3. Loosen the air cleaner intake duct clamp.
4. Remove the air cleaner intake duct from the air cleaner cover.
5. Remove the air cleaner intake duct from the throttle body.

1. Install the air cleaner intake duct to the throttle body. NOTE: Refer to «FASTENER NOTICE»(/chevrolet/impala/viii-1999-2006/remont/oem-general-information/#gm-vehicles-cautions-notices__fastener-notice) .
2. Install the air cleaner intake duct to the air cleaner cover. Tighten the air cleaner duct clamp to 2 N.m (18 lb in).
3. Install the IAT sensor.
4. Connect the IAT sensor electrical connector (3).

SUPERCHARGER

Removal (3.8L - VIN 1)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) under FUEL SYSTEMS. Remove fuel injector sight shield (upper engine cover) from engine. Remove the Exhaust Gas Recirculation (EGR) valve heat shield nut, bolt and the heat shield.
2. Lift or rotate the supercharger drive belt tensioner using a 15-mm box end wrench on the pulley nut. Remove the supercharger drive belt. Remove the right spark plug wires from the ignition coils and reposition. Remove the MAP sensor bracket. Remove the fuel rail assembly. See «FUEL RAIL & INJECTORS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-rail-injectors) under FUEL SYSTEMS.
3. Disconnect the vacuum lines and wiring harness connectors as necessary. Remove the accelerator and the cruise control cables with the bracket from the throttle body. Remove the air cleaner intake duct. Remove the supercharger bolts. Remove the supercharger. Remove the supercharger gasket.
4. Remove the supercharger "O" ring seals. Clean the supercharger mating surfaces. If replacing the supercharger remove the throttle body, PCV valve, supercharger bypass valve and manifold vacuum source.

1. If replacing the supercharger, install the manifold vacuum source, supercharger bypass valve, PCV valve and throttle body. Install the new supercharger "O" ring seals. Install the new supercharger gasket. Do not use any sealer on the gasket. Install the supercharger.
2. Loosely install the supercharger right-side bolts. Loosely install the supercharger left-side bolts. Tighten the supercharger bolts starting from the center and working to the outside of the supercharger to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
3. Install the air cleaner intake duct. Install the accelerator and the cruise control cables with the bracket to the throttle body. Connect the vacuum hoses and electrical connectors as necessary. Install the fuel rail assembly. See «FUEL RAIL & INJECTORS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-rail-injectors) under FUEL SYSTEMS.
4. Install the MAP sensor bracket. Install the spark plug wires to the ignition coils. Install the supercharger drive belt. Install the EGR valve heat shield, nut and bolt. Tighten the EGR heat shield nut and bolt to specification. Install the fuel injector sight shield. Connect the negative battery cable. Inspect for fluid or vacuum leaks.

Removal & Installation (3.8L - VIN 1)

Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the boost source and signal hoses from the boost control solenoid. (Scheme 13) Disconnect the boost control solenoid electrical connector. Remove the boost control solenoid retaining nut. Remove the boost control solenoid. To install, reverse removal procedure.

Scheme 4

1. Remove the boost control solenoid. See «BOOST CONTROL SOLENOID»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation). Disconnect the vacuum hose from the bypass valve actuator. (Scheme 13)
2. Remove the bypass valve actuator mounting bolts and rotate the bypass valve actuator until the rod disengages the lever. To install, reverse removal procedure. Tighten the bypass valve actuator mounting bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).

POWERTRAIN CONTROL MODULE

PCM is located inside air cleaner housing assembly. (Scheme 14) Turn OFF the ignition. Disconnect negative battery cable. Remove the left upper fender brace. Remove the air cleaner housing cover assembly. Without disconnecting the PCM connectors, remove the PCM and harness from the air cleaner housing. Disconnect the PCM electrical connectors.

1. Connect the PCM electrical connectors to the PCM. Tighten connectors to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the PCM and harness into the air cleaner housing. Install the air cleaner housing cover.
2. Install the left upper fender brace. Reconnect the negative battery cable. If a new PCM is being installed, program the PCM. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Scheme 5

See CAMSHAFT POSITION SENSOR under IGNITION SYSTEMS.

See CRANKSHAFT POSITION SENSOR under IGNITION SYSTEMS.

ENGINE COOLANT TEMPERATURE SENSOR

Note. Recover and store used coolant in a used coolant holding tank and submit the used coolant for recycling on a regular basis. Do not pour used coolant down the drain. Ethylene glycol antifreeze is very toxic. Disposing of ethylene glycol into the sewer system or ground water is both illegal and ecologically unsound.

Turn OFF the ignition. Partially drain the cooling system to below the Engine Coolant Temperature (ECT) sensor. (Scheme 15)or (Scheme 16). Disconnect the ECT sensor electrical connector. Carefully remove the ECT sensor.

Note. Replacement components must be the correct part number for the application. Components requiring the use of the thread locking compound, lubricants, corrosion inhibitors, or sealants are identified in the service procedure. Some replacement components may come with these coatings already applied. Do not use these coatings on components unless specified. These coatings can affect the final torque, which may affect the operation of the component. Use the correct torque specification when installing components in order to avoid damage.

Coat the ECT sensor threads with Thread Sealer (12346004) or the equivalent. Install the ECT sensor. Tighten the ECT sensor to specification. See TORQUE SPECIFICATIONS . Connect the ECT sensor electrical connector. Refill the engine coolant system. See COOLING SYSTEM BLEEDING under COOLING SYSTEM.

Scheme 6

Scheme 7

See FUEL LEVEL SENSOR under FUEL SYSTEMS.

See FUEL TANK PRESSURE SENSOR under FUEL SYSTEMS.

HEATED OXYGEN SENSOR

Removal (3.1L & 3.4L)

Turn OFF the ignition. HO2S 1 is located in exhaust manifold. (Scheme 17) HO2S 2 is located behind catalytic converter. (Scheme 18) If removing HO2S 2, raise and support vehicle. On all sensors, disconnect the HO2S harness connector. Using Heated Oxygen Sensor Wrench (J-39194-B), remove the HO2S.

1. A special anti-seize compound is used on the oxygen sensor threads. The compound consists of a liquid graphite and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New sensors will have the compound applied to the threads.
2. If a sensor is removed and is to be reinstalled, the threads must have an anti-seize compound applied before installation. Coat the threads of the HO2S with Anti-Seize Compound (12377953), if necessary.
3. Install the HO2S and tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Connect HO2S harness connector. Lower vehicle, if necessary.

Scheme 8

Scheme 9

Removal (3.8L)

Turn OFF the ignition. HO2S 1 is located in exhaust manifold. (Scheme 19) HO2S 2 is located behind catalytic converter. (Scheme 20) Remove fuel injector sight shield (upper engine cover) from engine. If removing HO2S 2, raise and support vehicle. On all sensors, disconnect the HO2S harness connector. Using Heated Oxygen Sensor Wrench (J-39194-B), remove the HO2S.

1. A special anti-seize compound is used on the oxygen sensor threads. The compound consists of a liquid graphite and glass beads. The graphite will burn away, but the glass beads will remain, making the sensor easier to remove. New sensors will have the compound applied to the threads.
2. If a sensor is removed and is to be reinstalled, the threads must have an anti-seize compound applied before installation. Coat the threads of the HO2S with Anti-Seize Compound (12377953), if necessary.
3. Install the HO2S and tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Connect HO2S harness connector. Lower vehicle, if necessary.

Scheme 10

Scheme 11

Removal & Installation (3.1L)

The Intake Air Temperature (IAT) sensor is located in the air intake duct between the air cleaner assembly and the throttle body. (Scheme 21) Disconnect the IAT sensor harness connector. Carefully grasp the sensor and with a twisting and pulling motion, remove the IAT sensor from air intake duct. To install, reverse removal procedure.

Scheme 12

Removal & Installation (3.4L & 3.8L)

The Intake Air Temperature (IAT) sensor is mounted in the air intake duct. Disconnect the IAT sensor harness connector. Carefully grasp the sensor and with a twisting and pulling motion, remove the IAT sensor from air intake duct. To install, reverse removal procedure.

See KNOCK SENSOR under IGNITION SYSTEMS.

Turn OFF the ignition. Remove the screws that attach the Manifold Absolute Pressure (MAP) sensor to the bracket. (Scheme 22) Disconnect the MAP sensor electrical connector. Disconnect the MAP sensor inlet vacuum hose. Remove the MAP sensor from the bracket.

Position the MAP sensor to the bracket. Connect the MAP sensor inlet vacuum hose. Connect the MAP sensor electrical connector. Install the MAP sensor screws. Tighten the screws to specification. See TORQUE SPECIFICATIONS .

Scheme 13

Removal (3.8L - VIN K)

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the MAP sensor electrical connector. (Scheme 23) Carefully release the locking tabs holding the MAP sensor to the PCV valve cover just enough to remove the MAP sensor. Pull the MAP sensor straight out of PCV valve cover.

Ensure that the seal is installed on the MAP sensor and that the seal is not damaged. Position and install the MAP sensor to the PCV valve cover. Ensure that the locking tabs engage to hold the MAP sensor to the PCV valve cover. Connect the MAP sensor electrical connector. Install the fuel injector sight shield.

Scheme 14

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Manifold Absolute Pressure (MAP) sensor electrical connector. (Scheme 24) Disconnect the MAP sensor vacuum hose. Remove the MAP sensor screws. Remove the MAP sensor from the bracket.

Install the MAP sensor. Install the MAP sensor screws. Tighten the screws to specification. See TORQUE SPECIFICATIONS . Connect the MAP sensor electrical connector and the vacuum hose. Install the fuel injector sight shield.

Scheme 15

Removal (3.1L)

Turn OFF the ignition. Remove the PCV valve tube from the air intake duct. (Scheme 21) Disconnect the Intake Air Temperature (IAT) sensor harness connector. Disconnect the Mass Airflow (MAF) sensor harness connector. Remove the air inlet duct from the air cleaner housing and the MAF sensor. Remove the MAF sensor from the air filter housing.

Install the MAF sensor to the air cleaner intake duct. Install the air cleaner intake duct to the air cleaner housing and the throttle body. Tighten the clamps to specification. See TORQUE SPECIFICATIONS . Connect the MAF sensor electrical connector. Connect the IAT sensor electrical connector. Start and idle the engine. Inspect the air cleaner intake duct for leaks.

Removal (3.4L)

Turn OFF the ignition. Disconnect the Intake Air Temperature (IAT) sensor electrical connector. Disconnect the Mass Airflow (MAF) sensor electrical connector. (Scheme 25) Remove the air inlet duct from the MAF sensor and the throttle body. Remove the MAF sensor from the air filter housing.

Install the MAF sensor to the air filter housing. Install the air inlet duct to the MAF sensor and the throttle body. Connect the IAT sensor electrical connector. Connect the MAF sensor electrical connector. Start and idle the engine. Inspect the air intake duct for leaks.

Scheme 16

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Mass Airflow (MAF) sensor electrical connector. (Scheme 26) Remove the MAF sensor screws. Remove the MAF sensor.

Install the MAF sensor. Install the MAF sensor screws. Tighten the screws to specification. See TORQUE SPECIFICATIONS . Connect the MAF sensor electrical connector. Install the fuel injector sight shield.

Scheme 17

Turn OFF the ignition. Disconnect the fuel lines. See FUEL LINE DISCONNECT FITTINGS under FUEL SYSTEMS. Disconnect the Throttle Position (TP) sensor electrical connector. (Scheme 27) Remove the 2 TP sensor screws. Remove the TP sensor and "O" ring.

Install the new TP sensor "O" ring on the TP sensor. Install the TP sensor on the throttle body assembly. Install the 2 TP sensor screws, using Loctite® 262 Thread-Locking Compound (12345493), or equivalent on the screws. Tighten the TP sensor attaching screws to specification. See TORQUE SPECIFICATIONS . Connect the TP sensor electrical connector. Connect the fuel lines. Install the air intake duct. Reconnect the IAT sensor connector.

Scheme 18

Turn OFF the ignition. Remove the air intake duct. Disconnect the EVAP purge line. Disconnect the fuel lines. See FUEL LINE DISCONNECT FITTINGS under FUEL SYSTEMS. Disconnect the TP sensor electrical connector. (Scheme 27) Remove the 2 TP sensor screws. Remove the TP sensor and "O" ring.

Install the TP sensor "O" ring on the TP sensor. Install the TP sensor on the throttle body assembly. Install the 2 TP sensor screws, using Loctite® 262 Thread-Locking Compound (12345493), or equivalent on the screws. Tighten the TP sensor attaching screws to specification. See TORQUE SPECIFICATIONS . Connect the TP sensor electrical connector. Connect the EVAP purge line. Connect the fuel lines. Install the air intake duct.

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Throttle Position (TP) sensor electrical connector. (Scheme 26) Remove the 2 TP sensor screws. Remove the TP sensor.

Install the TP sensor. Apply Loctite® 262 Thread-Locking Compound (12345493) or equivalent to the TP sensor screws. Install the 2 TP sensor screws. Tighten the screws to specification. See TORQUE SPECIFICATIONS . Connect the TP sensor electrical connector. Install the fuel injector sight shield.

COOLING SYSTEM BLEEDING

Note. Recover and store used coolant in a used coolant holding tank and submit the used coolant for recycling on a regular basis. Do not pour used coolant down the drain. Ethylene glycol antifreeze is very toxic. Disposing of ethylene glycol into the sewer system or ground water is both illegal and ecologically unsound.

1. Ensure the radiator drain cock is closed. Remove the radiator cap. Open the air bleed valve on the thermostat housing 2 full turns. Open the air bleed valve above the water pump 2 full turns. Slowly add a 50/50 mixture of GM Goodwrench Dex-Cool® and deionized water to the radiator until the coolant level is at the base of the radiator fill neck.
2. Close the cooling system bleeder screws. Install the coolant pressure cap. Start the engine. Run the engine at 2000-2500 RPM until the engine reaches normal operating temperature. Allow the engine to idle for 3 minutes. Shut the engine off. Allow the engine to cool.
3. Top off the coolant as necessary. Inspect the concentration of the engine coolant using Coolant Tester (J-23688). Rinse away any excess coolant from the engine and the engine compartment. Inspect the cooling system for leaks.

1. The Camshaft Position (CMP) sensor is located at top rear of cylinder block. (Scheme 28) Turn ignition off. Remove the accessory drive belt from the power steering pump.
2. Remove the power steering pump. See appropriate POWER RACK & PINION article in STEERING. Disconnect the CMP sensor electrical connector. Remove the attaching bolt. Remove the CMP sensor. Inspect the sensor "O" ring for wear, cracks, or leakage if the sensor is not being replaced.

Note. Inspect the CMP sensor "O" ring for wear or damage. If a problem is found, replace the "O"ring.

Lubricate the "O" ring with clean engine oil. Install the CMP sensor. Tighten the CMP sensor retaining bolt to specification. See TORQUE SPECIFICATIONS . Connect the CMP sensor electrical connector. Install the power steering pump to the vehicle.

Scheme 19

Remove the coolant recovery reservoir. Remove the drive belt. Disconnect the electrical connector from the Camshaft Position (CMP) sensor. (Scheme 29) Remove the CMP sensor bolt. Remove the CMP sensor from the engine front cover.

Install the CMP sensor to the engine front cover. Install the CMP sensor bolt. Tighten the bolt to specification. See TORQUE SPECIFICATIONS . Connect the electrical connector to the CMP sensor. Install the drive belt. Install the coolant recovery reservoir.

Scheme 20

Removal (3.1L & 3.4L - CKP Sensor "A")

1. Crankshaft Position (CKP) sensor "A" may also be referred to as CKP sensor 24X. CKP sensor is located behind the crankshaft balancer. (Scheme 30) Turn OFF the ignition. Remove the drive belt. Raise and support the vehicle. Remove the lower air deflector. Disconnect the CKP sensor harness connector.
2. Remove the crankshaft balancer bolt. Using Crankshaft Balancer Puller (J-24420-C), remove the crankshaft balancer. Note the routing of the CKP sensor harness before removal. Remove the harness retaining clip and bolt. Disconnect the CKP sensor electrical connector. Remove the sensor bolts. Remove the CKP sensor.

1. Install the CKP sensor with bolts and the route harness as noted during removal. Install the harness retaining clip and bolt. Tighten the bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
2. Connect the CKP sensor electrical connector. Apply Sealer (12345739) or the equivalent to the keyway of the crankshaft balancer. Install the crankshaft balancer into position over the key in the crankshaft. Using Crankshaft Balancer Installer (J-29113), install the crankshaft balancer to the crankshaft.
3. Remove the crankshaft balancer installer from the crankshaft balancer. Install the crankshaft balancer washer and the crankshaft balancer bolt. Tighten the bolt to specification.
4. Install the lower air deflector. Lower the vehicle. Install the drive belt. Perform the CKP System Variation Learn Procedure. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Scheme 21

Removal (3.1L - CKP Sensor "B")

1. The Crankshaft Position (CKP) sensor "B" may also be referred to as CKP sensor 7X. CKP sensor is mounted in cylinder block. (Scheme 31) Turn the steering wheel fully to the left. Raise and support the vehicle. Remove the right front tire and wheel.
2. Disconnect the CKP sensor electrical connector. Remove the CKP sensor attaching bolt. Remove the CKP sensor from the engine. Inspect for wear, cracks, or leakage if the sensor is not being replaced.

1. Replace the "O" ring, if it is damaged. Lubricate the "O" ring with clean engine. Install the sensor to the block. Install the CKP sensor attaching bolt. Tighten the bolt to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
2. Install the CKP sensor electrical connector. Install right front tire and wheel. Lower the vehicle. Perform the CKP System Variation Learn Procedure. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Scheme 22

1. Turn OFF the ignition. Disconnect the negative battery cable. Remove the drive belt. Raise and support the vehicle. Remove the right front tire and wheel. Remove the right engine splash shield retainers and the engine splash shield. Remove the torque converter cover. Install the Flywheel Holder (J-37096) to hold the flywheel.
2. Remove the crankshaft balancer retaining bolt. Install the Crankshaft Balancer Remover (J-38197-A). Remove the crankshaft balancer. Remove the crankshaft balancer remover. Disconnect the Crankshaft Position (CKP) sensor electrical connector. Remove the CKP sensor shield. (Scheme 32) DO NOT use a pry bar. Remove the CKP sensor studs. Remove the CKP sensor.

Scheme 23

1. Install the CKP sensor. Install the CKP sensor studs. Tighten the studs to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the CKP sensor shield. Connect the CKP sensor electrical connector.
2. Coat the engine front cover seal contact area on the crankshaft balancer, and the seal surface with clean engine oil. Install the crankshaft balancer. Install the crankshaft balancer retaining bolt. Use the Flywheel Holder (J-37096) to keep the flywheel from turning. Tighten the crankshaft balancer bolt to specification.
3. Remove the flywheel holder. Install the torque converter cover. Install the right engine splash shield and the engine splash shield retainers. Install the right front tire and wheel. Lower the vehicle. Install the drive belt. Reconnect the negative battery cable. Perform the CKP System Variation Learn Procedure. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

1. Turn OFF the ignition. Disconnect the spark plug wires from the ignition coils. Note the position from which the wires are removed. Remove the 2 screws that secure the ignition coil to the ignition control module. Remove the ignition coil.
2. To install, reverse removal procedure. Tighten the coil screws to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Connect the spark plug wires to the ignition coils. (Scheme 33)or (Scheme 34).

Scheme 24

Scheme 25

1. Disconnect all the electrical connectors at the Ignition Control Module (ICM). Note the position of the spark plug wires for installation and disconnect the spark plug wires from the ignition coils. Remove the screws securing the coil assemblies to the ignition control module.
2. Disconnect the coils from the ignition control module. Remove the fasteners securing the ignition control module assembly to the engine. Remove the ignition control module from the bracket.
3. To install, reverse removal procedure. Tighten the ignition coil screws to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Connect the spark plug wires to the ignition coils. (Scheme 33)or (Scheme 34).

Turn OFF the ignition. Raise and support the vehicle. Disconnect the wiring harness connector from the knock sensor. (Scheme 35) Remove the knock sensor from the engine block.

Note. Do not apply thread sealant to the sensor threads. The sensor threads are coated at the factory and applying additional sealant affects the sensor's ability to detect detonation.

Install the knock sensor into the engine block. Tighten the knock sensor to specification. See TORQUE SPECIFICATIONS . Connect the knock sensor wiring harness connector to the knock sensor. Lower the vehicle.

Scheme 26

Removal & Installation (3.8L)

1. Turn OFF the ignition. Raise and support the vehicle. Drain the cooling system. Locate Knock Sensor (KS) to be removed. (Scheme 36)or (Scheme 37). Disconnect the KS electrical connector. Remove the KS.
2. To install, reverse removal procedure. Tighten the KS to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Connect the KS electrical connector. Lower the vehicle. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__cooling-system-bleeding) under COOLING SYSTEM.

Scheme 27

Scheme 28

1. Turn OFF the ignition. To remove spark plugs from left cylinder bank (front cylinder head), remove the spark plug wires from spark plugs. Remove spark plugs from engine. To remove spark plugs from the right cylinder bank (rear cylinder head), remove the throttle body air inlet duct.
2. Remove wiper motor cover assembly. See appropriate WIPER/WASHER SYSTEMS article in ACCESSORIES & EQUIPMENT. Set the park brake. Shift the transaxle into Neutral. Remove the engine mount strut bolts. (Scheme 38) Swing the engine mount struts aside. Install the Engine Tilter Strap (J-41131) to the engine. (Scheme 39)
3. Pull on the engine in order to rotate the engine forward. Tighten the engine tilter strap. Remove the spark plug wires from the spark plugs. Remove the spark plugs from the engine.

Scheme 29

Scheme 30

1. Gap the spark plugs to.060" (1.52 mm). Install the spark plugs. Tighten the spark plugs to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the spark plug wires to the spark plugs. Return the engine to the proper position.
2. Remove the engine tilter strap from the engine. Swing the engine mount struts in position. Install the engine mount strut bolts and tighten bolts to specification. Install wiper motor cover assembly. See appropriate WIPER/WASHER SYSTEMS article in ACCESSORIES & EQUIPMENT.

Removal (3.4L & 3.8L)

Turn OFF the ignition. Note position of the spark plug wires before removing the wires. Twist the spark plug boot 1/2 turn before removing the boot. Remove the spark plug wires from the spark plugs. Remove the spark plugs from the engine.

Gap the spark plugs to.060" (1.52 mm). Install the spark plugs. Tighten the spark plugs to specification. See TORQUE SPECIFICATIONS . Install the spark plug wires to the spark plugs.

FUEL SYSTEMS

FUEL SYSTEM PRESSURE RELEASE

1. Turn OFF the ignition. Disconnect the negative battery cable in order to avoid possible fuel discharge if an accidental attempt is made to start the engine. On 3.8L, remove fuel injector sight shield (upper engine cover) from engine. On all models, install Fuel Pressure Gauge Adaptor (J-34730-262) to the fuel pressure connection on the fuel rail.
2. Connect Fuel Pressure Gauge (J-34730-1A) to the fuel pressure connection. Wrap a shop towel around the fuel pressure connection while connecting the fuel pressure gauge in order to avoid spillage. Install the bleed hose into an approved container and open the valve to bleed the system pressure.
3. The fuel connections are now safe for servicing. Drain any fuel remaining in the fuel pressure gauge into an approved container. Remove the fuel pressure gauge and adaptor.

Removal (Quick-Connect Fitting - With Metal Collar)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Remove the retainer from the quick-connect fitting. Blow any dirt out of the fitting, using compressed air.
2. Choose the correct Quick-Connect Separator tool from Tool Set (J-37088-A) for the size of the fitting. Insert the quick-connect separator into the female connector, then push inward to release the locking tabs. (Scheme 40)
3. Pull the connection apart. Using a clean shop towel, wipe off the male pipe end. Inspect both ends of the fitting for dirt and burrs. If necessary, remove rust or burrs from the fuel pipes with an emery cloth. Use a radial motion with the fuel pipe end in order to prevent damage to the "O" ring sealing surface. Clean or replace the components and assemblies as required.

Apply a few drops of clean engine oil to the male pipe end. Push both sides of the fitting together to cause the retaining tabs to snap into place. Once installed, pull on both sides of the fitting to make sure the connection is secure. Install the retainer over the quick-connect fitting.

Scheme 31

Removal (Quick-Connect Fitting - With Plastic Collar)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Using compressed air, blow any dirt out of the quick-connect fitting.
2. Squeeze the plastic tabs of the male end connector. (Scheme 41) Pull the connection apart. Using a clean shop towel, wipe off the male pipe end. Inspect both ends of the fitting for dirt and burrs.
3. If necessary, remove rust or burrs from the fuel pipes with an emery cloth. Use a radial motion with the fuel pipe end in order to prevent damage to the "O" ring sealing surface. Clean or replace the components and assemblies as required.

Apply a few drops of clean engine oil to the male pipe end. Push both sides of the fitting together to cause the retaining tabs to snap into place. Once installed, pull on both sides of the fitting to make sure the connection is secure.

Scheme 32

FUEL FILLER TUBE

Note. Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering the open pipes and passages.

1. Drain the fuel tank. See «FUEL TANK DRAINING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-tank-draining) . Raise and support vehicle. Loosen the fuel filler hose clamp at the fuel tank. Loosen the fuel filler hose clamp at the filler pipe.
2. Disconnect the vapor recirculation line at the fuel filler pipe, if equipped. Remove the fuel filler hose. Remove the fuel filler pipe attaching screw from the underbody. Lower vehicle. Remove the fuel filler pipe attaching screws from the fuel filler pipe access panel. Remove the fuel filler pipe.

1. Install the fuel filler pipe. Install the fuel filler pipe attaching screws to the fuel filler pipe access panel. Tighten the fuel filler pipe attaching screws to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).
2. Install the fuel filler pipe attaching screw to the underbody. Tighten the fuel filler pipe attaching screw to specification. Connect the vapor recirculation line at the fuel filler pipe, if equipped. Install the fuel filler hose. Inspect and make sure filler hose is fully seated on fuel tank port, and fuel filler pipe.
3. Make sure clamp is properly located on tank port between the bead and tank. (Scheme 42) Tighten the fuel tank filler hose clamps to specification. Lower the vehicle. Refill the fuel tank and install the fuel fill cap.

Scheme 33

FUEL FILTER

Note. There is no service interval for fuel filter replacement. Only replace the fuel filter if the filter is restricted.

1. Fuel filter is located underneath vehicle. (Scheme 43) Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Raise and support the vehicle.
2. Disconnect the quick-connect fitting at the inlet of the fuel filter. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation). Remove the threaded nut fitting at the outlet of the fuel filter.
3. Drain any remaining fuel into an approved gasoline container. Remove the fuel filter mounting bracket bolt. Remove the fuel filter and the mounting bracket. Remove the fuel filter from the fuel filter mounting bracket.

Note. Cap the fittings and plug the holes when servicing the fuel system in order to prevent dirt and other contaminants from entering the open pipes and passages.

1. Remove the protective caps from the new fuel filter. Install the fuel filter into the fuel filter mounting bracket. Install the fuel filter and mounting bracket. Install the fuel filter mounting bracket attaching nut. Tighten the nut to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
2. Connect the quick-connect fitting at the inlet side of the fuel filter. Install the threaded nut fitting to the outlet of the fuel filter. Use a back-up wrench in order to prevent the fuel filter from turning. Tighten the fuel filter outlet pipe fitting to specification.
3. Lower the vehicle. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks.

Scheme 34

1. Remove fuel sender assembly from fuel tank. See «FUEL SENDER ASSEMBLY»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation). Remove the fuel level sensor electrical connector retaining clip. Disconnect the fuel level sensor electrical connector from under the fuel sender cover.
2. Disconnect the fuel pump electrical connector. Remove the fuel level sensor from the fuel sender assembly. (Scheme 44) To install, reverse removal procedure.

Scheme 35

1. The fuel pressure regulator is located on end of fuel rail. (Scheme 45) Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Disconnect the fuel pressure regulator vacuum line.
2. Remove the fuel pressure regulator retaining screw. Using a shop towel to catch any spilled fuel, lift and twist the fuel pressure regulator in order to remove the fuel pressure regulator from the fuel rail. Remove the retainer and spacer bracket from the rail and discard.
3. Remove the fuel pressure regulator from the engine fuel return pipe. Remove the fuel pressure regulator inlet "O" ring and discard.

1. Check the filter screen for contamination. If contaminated, replace the fuel pressure regulator. Lubricate the new pressure regulator inlet "O" ring with clean engine oil and install on the regulator inlet. Install the fuel return pipe to the regulator.
2. Install the new retainer and spacer bracket into the slot on the fuel rail. Install the pressure regulator to the fuel rail. Tighten the engine fuel return pipe nut to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
3. Connect the fuel pressure regulator vacuum line. Install the pressure regulator attaching screw. Tighten the pressure regulator attaching screw to specification. Inspect and verify that the retainer and spacer bracket is engaged in the slots in the fuel rail.
4. Grasp and pull on the regulator to ensure that the regulator is properly seated. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks.

Scheme 36

1. The fuel pressure regulator is located on the fuel rail. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Clean any dirt from the fuel pressure regulator retaining ring. Remove the vacuum line from the pressure regulator.
2. Remove the snap ring. (Scheme 46) Using a shop towel to catch any spilled fuel, lift and twist the fuel pressure regulator in order to remove the fuel pressure regulator from the fuel pressure regulator housing.
3. Remove the regulator small "O" ring. Remove the regulator filter screen. Remove the regulator large "O" ring. Remove the regulator back-up "O" ring. Cover the fuel pressure regulator housing to prevent contamination from entering the fuel system.

1. If a new fuel pressure regulator is not being installed, install new "O" rings on the fuel pressure regulator. Lubricate the "O" rings lightly with clean engine oil. Install the regulator back-up "O" ring. Install the regulator large "O" ring. Install the regulator filter screen. Install the regulator small "O" ring. Install the fuel pressure regulator in the fuel pressure regulator housing. Install the snap ring.
2. Connect the vacuum line to the fuel pressure regulator. Tighten the fuel fill cap. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install the fuel injector sight shield.

Scheme 37

The fuel pump is attached to the fuel sender assembly inside the fuel tank. See FUEL SENDER ASSEMBLY for removal and installation.

FUEL RAIL & INJECTORS

Note. An 8-digit identification number is located on the left side fuel rail assembly. Refer to this identification number if servicing or part replacement is required. Fuel injector "O" rings should always be replaced whenever the fuel injectors are serviced.

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Remove the upper intake manifold. See appropriate article in ENGINES. Disconnect the engine fuel feed pipe at the fuel rail. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation).
2. Disconnect the engine fuel return pipe at the fuel pressure regulator. Remove the fuel feed pipe and fuel return pipe "O" rings and discard. Disconnect the main injector harness electrical connector. To disconnect fuel injector connector, pull up the lock release of the fuel injector connector. Depress the lock tab and lift the connector from the injector. Disconnect all remaining fuel injector connectors.
3. Remove the injector electrical harness from the fuel rail. Disconnect the engine coolant temperature sensor electrical connector. Remove the fuel rail retaining bolts. (Scheme 47) Remove the fuel rail assembly. Remove the injector "O" ring seal from the spray tip end of each injector. Discard the lower "O" ring seals.
4. To remove injector(s) from the fuel rail, remove the fuel injector retainer clip. Remove the fuel injector from the fuel rail. Remove and discard the fuel injector upper "O" ring.

1. Lubricate the new injector upper "O" ring seal with clean engine oil. Install the new injector "O" ring seal on the injector. Install retainer clip on the injector. Push the fuel injector into the fuel rail injector socket with the electrical connector facing outward. The retainer clip locks on to a flange on the fuel rail injector socket.
2. Install the fuel rail assembly into the intake manifold. Tilt the rail assembly to install the injectors. Install the fuel rail attaching bolts. Tighten the fuel rail attaching bolt to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
3. Connect the engine coolant temperature sensor electrical connector. Install the injector electrical harness to the fuel rail. Connect the fuel injector connectors. Push the slide locks into position. Connect the main injector harness electrical connector. Install the new "O" rings on the fuel feed pipe and fuel return pipe.
4. Connect the fuel feed pipe at the fuel rail. Tighten the fuel feed pipe nut to specification. Connect the fuel return pipe at the fuel pressure regulator. Tighten the fuel return pipe nut to specification. Install the upper intake manifold. See appropriate article in ENGINES. Connect the negative battery cable.
5. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks.

Scheme 38

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) . Clean the fuel rail assembly and connections. Disconnect the fuel feed pipe and return pipe at the fuel rail. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
2. Disconnect the vacuum line from the fuel pressure regulator. Remove the ignition coil wires. Disconnect the 6 injector electrical connectors. Remove the fuel rail hold-down bolts. Remove the fuel rail with equal force on both sides of the fuel rail.
3. To remove injector(s) from the fuel rail, remove the fuel injector retainer clip. Remove the fuel injector from the fuel rail. Remove and discard the fuel injector upper "O" ring.

1. Lubricate the new injector upper "O" ring seal with clean engine oil. Install the new injector "O" ring seal on the injector. Install retainer clip on the injector. Push the fuel injector into the fuel rail injector socket with the electrical connector facing outward. The retainer clip locks on to a flange on the fuel rail injector socket.
2. "O" rings must be replaced on all components that are serviced. Lightly oil the fuel injector "O" rings with clean engine oil. Place the fuel rail assembly on the intake manifold. Seat the fuel injectors by hand. Install the fuel rail hold-down bolts.
3. Tighten the fuel rail hold-down bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Connect the 6 fuel injector electrical connectors. Connect the fuel feed and return pipes to the fuel rail tubes. Connect the vacuum line to the fuel pressure regulator. Install the ignition coil wires.
4. Tighten the fuel fill cap. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install the fuel injection sight shield.

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Clean the fuel rail assembly and connections. Disconnect the fuel feed pipe and return pipe at the fuel rail. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation).
2. Disconnect the vacuum line from the fuel pressure regulator. Remove the ignition coil wires and retainer clips on top of the supercharger. Remove the EVAP canister purge solenoid valve. (Scheme 48)
3. Remove the generator brace. (Scheme 49) Remove the boost control solenoid. (Scheme 13) Remove the bypass valve actuator. Disconnect the fuel injector electrical connectors. Remove the fuel injector electrical harness clips holding harness to front and the rear of the fuel rail.
4. Remove the engine mount strut bolt and nut from the left engine mount strut. (Scheme 50) Reposition the wiring harness from the left engine mount strut bracket. Remove the fuel rail hold-down nuts. Remove the fuel rail hold-down stud. Remove the fuel rail with equal force on both sides of the fuel rail.
5. To remove injector(s) from the fuel rail, remove the fuel injector retainer clip. Remove the fuel injector from the fuel rail. Remove and discard the fuel injector upper "O" ring.

1. Lubricate the new injector upper "O" ring seal with clean engine oil. Install the new injector "O" ring seal on the injector. Install retainer clip on the injector. Push the fuel injector into the fuel rail injector socket with the electrical connector facing outward. The retainer clip locks on to a flange on the fuel rail injector socket.
2. The "O" rings must be replaced on all components that are serviced. Lightly oil the fuel injector "O" rings with clean engine oil. Place the fuel rail assembly on the intake manifold. Seat the fuel injectors by hand. Install the fuel rail hold-down nuts. Tighten the fuel rail hold-down nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).
3. Install the fuel rail hold-down stud. Tighten the stud to specification. Install the wiring harness to the engine mount strut. (Scheme 50) Install the left engine mount strut bolt and nut. Tighten the nut to specification. Install the fuel injector electrical harness clips holding harness to the front and the rear of fuel rail. Connect the 6 fuel injector electrical connectors.
4. Install the bypass valve actuator. (Scheme 13) Install the rear generator mounting bracket. (Scheme 49) Install the ignition coil wires to the coil, and the retainer clips to the top of supercharger. Connect the vacuum line to the fuel pressure regulator.
5. Connect the fuel feed pipe and return pipe to the fuel rail. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install the fuel injection sight shield.

Scheme 39

Scheme 40

Scheme 41

Removal (Century, Grand Prix & Regal)

1. Open the rear compartment lid. Remove the rear compartment convenience net. Remove the lower rear compartment convenience net retainers. Disconnect the cellular antenna cable from the communication interface module by pulling outward on the square plastic housing. (Scheme 51)
2. Disconnect the two lower connectors from the module. Disconnect the GPS antenna cable from the module by pulling outward on the circular metal sleeve. Remove the nuts from the module bracket. Remove the module and the bracket from the rear compartment. Remove the rear compartment mat from the rear compartment.
3. Remove the spare tire cover from the rear compartment. Remove the spare tire. Remove the retainers by the rear compartment lock striker. Fold the rear section of the rear compartment trim panel foreword. Fold each side of the trim panel toward the center of the car.
4. Remove the rear compartment trim panel from the rear compartment. (Scheme 52) Remove the fuel sender access panel nuts. Remove the fuel sender access panel.

1. Install the fuel sender access panel. Install the fuel sender access panel nuts. Tighten the nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Install the rear compartment trim panel to the rear compartment. (Scheme 52)
2. Unfold the trim panel sides and rear sections and press them into place. Install the spare tire. Install the spare tire cover in the rear compartment. Position the communication interface module and the bracket in the rear compartment. (Scheme 51) Install the communications interface module bracket nuts. Tighten the bracket nuts to specification.
3. Connect the GPS antenna cable by pushing in on the metal sleeve. Connect the two lower connectors to the module. Connect the cellular antenna by pressing in on the square plastic housing. Install the rear compartment mat in the rear compartment. Install the retainers by the rear compartment lock striker. Replace the lower rear compartment convenience net retainers. Install the rear compartment convenience net. Close the rear compartment.

Scheme 42

Scheme 43

Scheme 44

Removal (Impala & Monte Carlo)

1. Open the rear compartment lid. Pull up on the rear compartment sill plate to release the spring clips. Remove the rear compartment sill plate from rear compartment. (Scheme 54) Remove the convenience net and retainers, if equipped.
2. Remove the tail lamp retainers. Remove the plastic cover from the communication interface module (On-Star module). (Scheme 51) Remove the nuts from the module bracket. Lift the module off the studs. Disconnect the cellular antenna cable from the communication interface module by pulling outward on the square plastic housing.
3. Disconnect the two lower connectors from the module. Disconnect the GPS antenna cable from the module by pulling outward on the circular metal sleeve. Remove the module and the bracket from the rear compartment. Remove the spare tire cover from the rear compartment. Remove the rear seat cushion and rear seat back.
4. Remove the push-in retainers from the rear compartment trim panel. Pull back the trim panel from the rear seating area. Remove the trim panel from the rear compartment. (Scheme 55) Remove the fuel sender access panel nuts. Remove the fuel sender access panel.

1. Install the fuel sender access panel. Install the fuel sender access panel nuts. Tighten the nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the rear compartment trim panel to the installed position. Press the trim over the rear shock tower studs. Install the push-in retainers to the trim panel
2. Install the spare tire cover to the rear compartment. Install the rear seat cushion and the rear seat back. Position the communication interface module and the bracket in the rear compartment. Connect the GPS antenna cable by pushing in on the metal sleeve. Connect the two lower connectors to the module.
3. Connect the cellular antenna by pressing in on the square plastic housing. Install the nuts to the interface module bracket. Tighten the nuts to specification. Install the plastic cover on the communication interface module. Install the convenience net and retainers, if equipped. Install the tail lamp retainers. Install the sill plate. Close the rear compartment.

Scheme 45

Scheme 46

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release). Remove the fuel sender access panel. See «FUEL SENDER ACCESS PANEL»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation).
2. Disconnect the Fuel Tank Pressure (FTP) sensor electrical connector. Remove the FTP sensor. Disconnect the fuel sender electrical connector. Clean the fuel pipes, and fuel sender assembly to prevent possible fuel contamination during removal.
3. Disconnect the quick-connect fittings at the fuel sender assembly. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation). Hold down the fuel sender and remove the fuel sender retaining ring. Remove the fuel sender assembly. (Scheme 44) Clean the fuel sender assembly sealing surfaces. Inspect the fuel sender assembly sealing surfaces.
4. Remove the fuel sender assembly and seal from the fuel tank. Discard the fuel sender assembly seal. Clean and inspect the fuel sender sealing surfaces.

Note. Ensure that the fuel sender assembly retaining ring is fully seated within the tab slots on the fuel tank. Always replace the fuel sender seal when reinstalling the fuel sender assembly.

1. Position the new fuel sender seal on the fuel tank. Do not fold over or twist the fuel pump strainer when installing the fuel sender assembly, as this will restrict fuel flow. Also, ensure that the fuel pump strainer does not block full travel of float arm.
2. Install the fuel sender assembly. Install the fuel sender assembly retaining ring. Connect the fuel sender electrical connector. Connect the quick-connect fittings at the fuel sender. Connect the fuel tank pressure sensor electrical connector.
3. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition, with the engine OFF for 2 seconds. Turn OFF the ignition for 10 seconds. Turn ON the ignition, with the engine OFF. Inspect for fuel leaks.
4. Install the fuel sender access panel. See «FUEL SENDER ACCESS PANEL»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .

FUEL SYSTEM CLEANING

Note. When flushing the fuel tanks, handle the fuel and water mixture as a hazardous material. Handle the fuel and water mixture in accordance with all applicable local, state, and federal laws and regulations.

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) . Remove the fuel tank. See «FUEL TANK»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-tank) . Remove the fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
2. Inspect the fuel sender strainer. Replace a contaminated strainer and inspect the fuel pump. Inspect the fuel pump inlet for dirt and debris. Replace the fuel pump if you find dirt or debris in the fuel pump inlet. Flush the fuel tank with hot water. Pour the water out of the fuel sender assembly opening in the fuel tank. Rock the fuel tank in order to be sure that the removal of the water from the fuel tank is complete.
3. Allow the tank to dry completely before reassembly. Install the fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) . Install the fuel tank. See «FUEL TANK»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-tank) .

FUEL TANK

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) . Drain the fuel tank. See «FUEL TANK DRAINING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-tank-draining) . Raise and support vehicle.
2. Loosen the fuel filler hose clamp at the fuel tank. Remove the fuel tank filler hose from the fuel tank. Disconnect the filler vent pipe near the filler hose/pipe connection. Disconnect the quick-connect fittings at the fuel filter and chassis. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
3. Disconnect the EVAP pipe from the connection at the front of the fuel tank. Remove the rubber exhaust pipe hangers in order to allow the exhaust system to drop slightly. Separate the two halves of the EVAP fresh air hose at the splice. Remove the three push pins from the tank shield, and remove the shield.
4. Do not bend the fuel tank straps as this may damage the straps. With the aid of an assistant, support the fuel tank. Remove the fuel tank strap attaching bolts from the fuel tank straps. Disconnect the fuel sender and the fuel tank pressure sensor electrical connectors at the body pass through. Remove the fuel tank from the vehicle.

Note. Replace the vapor hoses with original equipment or parts meeting GM specifications. Use only reinforced fuel-resistant hose identified with the word Fluoroelastomer or GM 6163M on the hose.

1. Position and support the fuel tank with the aid of an assistant. Connect the fuel sender and the fuel tank pressure sensor electrical connectors. Install the fuel tank straps. Install the fuel tank strap bolts. Tighten the fuel tank strap bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).
2. Position the tank shield, and install the three push pins. Connect the quick-connect fittings at the fuel filter and chassis. Connect the EVAP pipe at the front of the fuel tank. Connect the fuel tank filler hose to the fuel tank. Connect the filler vent pipe at the filler hose/pipe connection.
3. Connect the two parts of the EVAP fresh air hose at the splice. Fully seat the filler hose on fuel tank port. Make sure clamp is properly located on tank port between the bead and tank. (Scheme 42)
4. Tighten the fuel tank filler pipe hose clamp to specification. Install the rubber exhaust pipe hangers. Lower the vehicle. Add fuel and install the fuel filler pipe cap. Connect the negative battery cable. Inspect for fuel leaks using the following procedure. Turn ON the ignition, for 2 seconds. Turn OFF the ignition, for 10 seconds. Turn ON the ignition. Inspect for fuel leaks.

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) . Drain the fuel tank. See «FUEL TANK DRAINING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-tank-draining) . Raise and support vehicle.
2. Loosen the fuel filler hose clamp at the fuel tank. Remove the fuel tank filler hose from the fuel tank. Disconnect the quick-connect fittings at the fuel filter and chassis. See «FUEL LINE DISCONNECT FITTINGS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) . Disconnect the EVAP pipe from the connection at the front of the fuel tank.
3. Remove the rubber exhaust pipe hangers in order to allow the exhaust system to drop slightly. Support the fuel tank with a suitable jack. Support the fuel tank strap bolts. Lower the fuel tank to access the EVAP connections. Disconnect the EVAP pipes from the rear of the fuel tank.
4. Disconnect the EVAP pipe from the fuel limiter vent valve. Disconnect the fuel filler neck EVAP pipe at the rear of the fuel tank. Lower, and remove the fuel tank from the vehicle.

1. Install the fuel tank to a suitable jack. Connect the EVAP pipes to the rear of the fuel tank. Connect the EVAP pipe to the fuel limiter vent valve. Connect the fuel filler EVAP pipe at the rear of the fuel tank. Raise the fuel tank to the original position.
2. Install the fuel tank retaining strap bolts. Tighten the fuel tank retaining strap bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Remove the jack from the fuel tank. Connect the quick-connect fittings at the fuel tank. Connect the EVAP pipe at the front of the fuel tank. Install the fuel tank filler hose to the fuel tank.
3. Inspect and make sure that the filler hose is fully seated on fuel tank port. Make sure the clamp is properly located on tank port between the bead and the tank. (Scheme 42) Tighten the hose clamp to specification. Install the exhaust pipe to the exhaust hangers. Inspect the fuel and EVAP pipes making sure they were not kinked or damaged during removal and installation.
4. Lower the vehicle. Add fuel and install the fuel fill cap. Connect the negative battery cable. Inspect for fuel leaks using the following procedure. Turn ON the ignition, for 2 seconds. Turn OFF the ignition, for 10 seconds. Turn ON the ignition. Inspect for fuel leaks. Install fuel injection sight shield.

FUEL TANK DRAINING

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__fuel-system-pressure-release) . Remove fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) . Use a hand-operated fuel pump device in order to drain the fuel through the fuel sender access panel.
2. Install the fuel sender assembly. Remove the fuel filler pipe cap. Add fuel. Install the fuel tank filler pipe cap. Connect the negative battery cable. Inspect for fuel leaks using the following procedure. Turn ON the ignition, for 2 seconds. Turn OFF the ignition, for 10 seconds. Turn ON the ignition. Inspect for fuel leaks.

Remove the fuel sender access panel. See FUEL SENDER ACCESS PANEL. Disconnect the electrical connector from the fuel tank pressure sensor. (Scheme 44) Remove the fuel tank pressure sensor from the fuel sender assembly. To install, reverse removal procedure.

On 3.8L, remove fuel injector sight shield (upper engine cover) from engine. On all models, remove the electrical connector from the Idle Air Control (IAC) valve. (Scheme 26)or (Scheme 27). Remove the IAC valve attaching screws. Remove the IAC valve from the throttle body. Remove the IAC valve "O" ring.

1. Measure the distance between the tip of the IAC valve pintle and the mounting surface. (Scheme 56) If the distance is more than 1.10" (28 mm), use finger pressure in order to slowly retract the pintle. The force required to retract the pintle of a new valve will not cause damage to the valve.
2. Lubricate the IAC valve "O" ring with clean engine oil. Install the IAC valve "O" ring on the IAC valve. Install the IAC valve. Install the IAC valve attaching screws and tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications). Connect the IAC valve electrical connector.
3. Perform the following IAC valve learn procedure. Turn ON the ignition, then OFF. Restart the engine and check for proper idle operation. On 3.8L, install the fuel injector sight shield.

Scheme 47

THROTTLE BODY

1. Partially drain the cooling system. Loosen the air cleaner intake duct clamps. Remove the PCV tube from the air cleaner intake duct, if necessary. Disconnect the Intake Air Temperature (IAT) sensor electrical connector. Disconnect the Mass Airflow (MAF) sensor electrical connector. Remove the air intake duct.
2. Disconnect the Idle Air Control (IAC) valve electrical connector. Disconnect the Throttle Position (TP) sensor electrical connector. Remove the accelerator control cable bracket. Disconnect the throttle body coolant by-pass hoses. Disconnect the heater pipe-to-throttle body nut. Remove the nuts and bolts holding the throttle body to the intake manifold. Remove the throttle body assembly. Remove the old gasket.

1. Clean the gasket surface on the intake manifold and the throttle body assembly. Install a new gasket, if necessary. Install the throttle body assembly. Install the throttle body retaining nuts and bolts. Tighten the throttle body retaining nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
2. Install the heater pipe-to-throttle body nut. Tighten the nut to specification. Connect the throttle body coolant by-pass hoses. Connect the IAC valve electrical connector. Connect the TP sensor electrical connector. Install the accelerator controls cable bracket. Install the air intake duct. Reconnect the IAT sensor connector.
3. Connect the PCV tube to the air cleaner intake duct, if necessary. Refill the coolant. See «COOLING SYSTEM BLEEDING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__cooling-system-bleeding) under COOLING SYSTEM. The throttle should operate freely without binding between full closed and wide open throttle.
4. Inspect for complete throttle opening and closing positions by operating the accelerator pedal. Also inspect for poor carpet fit under the accelerator pedal.

1. Remove fuel injector sight shield (upper engine cover) from engine. Partially drain the cooling system. Remove the air cleaner intake duct. Disconnect the Idle Air Control (IAC) valve electrical connector. (Scheme 26) Disconnect the Throttle Position (TP) sensor electrical connector.
2. Disconnect the Mass Airflow (MAF) sensor electrical connector. Remove the accelerator controls cable bracket. Disconnect the electrical harness retainer clip from the accelerator controls cable bracket, if applicable. Remove the vacuum hoses from the throttle body.
3. Remove the nut from the air injection pipe, if applicable. Remove the throttle body support bracket bolts. Remove the throttle body support bracket. Remove the throttle body nuts. Remove the throttle body assembly. Clean the throttle body gasket mating surfaces.

1. Install the new gasket. Install the throttle body assembly. Install the throttle body nuts. Tighten the nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the throttle body support bracket. Install the throttle body support bracket bolts. Tighten the bolts to specification.
2. Install the air injection pipe and the nut, if applicable. Tighten the nut to specification. Install the vacuum hoses to the throttle body. Install the accelerator controls cable bracket. Connect the electrical harness retainer clip and harness to the accelerator controls bracket, if applicable.
3. Connect the MAF sensor electrical connector. Connect the TP sensor electrical connector. Connect the IAC valve electrical connector. Install the air cleaner intake duct. Install the fuel injector sight shield. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__cooling-system-bleeding) under COOLING SYSTEM.

1. Remove fuel injector sight shield (upper engine cover) from engine. Partially drain the cooling system. Remove the air cleaner intake duct. Disconnect the Idle Air Control (IAC) valve electrical connector. (Scheme 26) Disconnect the Mass Airflow (MAF) sensor electrical connector.
2. Disconnect the Throttle Position (TP) sensor electrical connector. Remove the accelerator controls cable bracket. Remove the vacuum line from the throttle body. Remove the nut from the air injection pipe, if applicable. Remove the throttle body nuts. Remove the throttle body assembly. Clean the throttle body gasket mating surfaces.

1. Install the new gasket. Install the throttle body assembly. Install the throttle body nuts. Tighten the nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Install the accelerator controls cable bracket.
2. Install the air injection pipe and the nut to the throttle body, if applicable. Tighten the nut to specification. Install the vacuum line to the throttle body. Connect the IAC valve sensor electrical connector. Connect the MAF sensor electrical connector. Connect the TP sensor electrical connector.
3. Install the air cleaner intake duct. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__cooling-system-bleeding) under COOLING SYSTEM. Install the fuel injector sight shield.

THROTTLE BODY CLEANING PROCEDURE

1. Remove the air intake duct. Remove the air inlet screen, if applicable. Inspect the throttle body bore and the throttle valve plate for deposits. Open the throttle valve in order to inspect all of the surfaces.
2. Clean the throttle body bore and the throttle valve plate using a clean shop towel with GM Top Engine Cleaner (1052626) or an equivalent product. If the deposits are excessive, remove and disassemble the throttle body for cleaning. See «THROTTLE BODY»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__throttle-body) .
3. After disassembly, clean the throttle body using a parts cleaning brush. DO NOT immerse the throttle body in any cleaning solvent. If you removed and disassembled the throttle body for cleaning, assemble and install the throttle body. Install the air inlet screen, if applicable. Install the air intake duct.

EGR SYSTEM CLEANING

Whenever the Exhaust Gas Recirculation (EGR) valve is removed the EGR system should be inspected and cleaned if necessary. This will ensure that the EGR system will function properly under all operating conditions. Proper EGR system service consists of the following.

1. EGR System Diagnosis: Diagnosis of the EGR system should be performed if Powertrain Control Module (PCM) Diagnostic Trouble Codes (DTC) are set. See appropriate SELF-DIAGNOSTICS article.
2. EGR Valve Pipe Cleaning & Checking For Leaks Turn OFF the ignition. Clean and check the EGR pipe from the exhaust manifold to the EGR valve. See «EGR VALVE PIPE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) .
3. EGR Valve Cleaning If the EGR system is operating correctly, the EGR valve can be removed, checked for deposits, cleaned, and re-installed. Use the following procedure for this operation. Remove the EGR valve from the engine. See «EGR VALVE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__egr-valve) . While holding the EGR valve base in your hand, try to rotate the connector housing. Replace the valve if it exhibits looseness. Inspect the EGR valve pintle and seat for deposits. Use a cloth or other suitable soft device to remove deposits. Remove all loose particles. If the deposits are such that pintle/base interface cannot be cleaned adequately to allow the pintle to seal against the seat, replace the valve. Damage to the powdered metal EGR valve base will occur if cleaned with solvents, sharp tools, a wire brush or wheel, or by sand blasting. Cleaning by these methods is not recommended. Install EGR valve on the engine using a new gasket.

EGR VALVE

Note. Whenever the Exhaust Gas Recirculation (EGR) valve is removed, the EGR system should be inspected and cleaned if needed. This will ensure that the EGR system will function properly under all operating conditions. See EGR SYSTEM CLEANING .

Turn OFF the ignition. Disconnect the EGR valve electrical connector. (Scheme 57) Remove the bolt retaining the pipe assembly from the EGR valve and carefully pull the pipe back. Remove the EGR valve retaining bolts. Remove the EGR valve assembly. Remove the gasket. Clean the EGR valve mating surface.

Install the EGR valve with a new gasket to the intake manifold. Install the bolts through the EGR valve. Tighten the bolts to specification. See TORQUE SPECIFICATIONS . Connect the pipe assembly to the EGR valve. Install the bolt. Tighten the bolt to specification. Install the EGR valve electrical connector.

Scheme 48

Turn OFF the ignition. Disconnect the electrical connector from the Exhaust Gas Recirculation (EGR) valve. (Scheme 58) Remove the two EGR valve retaining nuts. Remove the EGR valve. Remove the gasket from the EGR valve adapter. Clean the EGR valve adapter from dirt and debris.

Install a new gasket on the EGR adapter. Install the EGR valve and two nuts. Tighten the nuts to specification. See TORQUE SPECIFICATIONS . Connect the EGR valve electrical connector.

Scheme 49

Removal & Installation (3.1L & 3.4L)

Turn OFF the ignition. Remove the bolt retaining the pipe assembly from the EGR valve and carefully pull the pipe assembly back. (Scheme 57) Unscrew the EGR pipe assembly nut from the exhaust manifold. Remove the EGR pipe. To install, reverse removal procedure. Tighten EGR pipe bolt/nut to specification. See TORQUE SPECIFICATIONS.

Removal (3.8L - Inlet Pipe)

Note. The EGR valve inlet pipe may also be referred to as the EGR valve adapter pipe.

1. Remove the Exhaust Gas Recirculation (EGR) valve. See «EGR VALVE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__egr-valve). If applicable, remove the Secondary Air Injection (AIR) pump outlet pipe. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation).
2. Remove the EGR valve outlet pipe. See «REMOVAL & INSTALLATION (3.8L - OUTLET PIPE)»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__removal-installation-38l-outlet). Remove the EGR valve inlet pipe mounting bolt from the exhaust manifold. (Scheme 59) Remove the mounting bolt, and the stud from the EGR valve inlet pipe bracket. Remove the EGR valve inlet pipe assembly.

1. Install the EGR valve inlet pipe assembly. Install the mounting bolt and the stud to the EGR valve inlet pipe bracket. Tighten the bolt and stud to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) .
2. Install the EGR valve inlet pipe bolt to the exhaust manifold. Tighten the bolt to specification. Install EGR valve outlet pipe. See «REMOVAL & INSTALLATION (3.8L - OUTLET PIPE)»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__removal-installation-38l-outlet) .
3. If applicable, install the AIR pump outlet pipe. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) . Install the EGR valve. See «EGR VALVE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__egr-valve) .

Scheme 50

Removal & Installation (3.8L - Outlet Pipe)

1. If applicable, remove the Secondary Air Injection (AIR) pump outlet pipe. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation). Remove the mounting bolt that attaches the Exhaust Gas Recirculation (EGR) outlet pipe flange to the intake manifold. (Scheme 60)
2. Remove the nut that attaches the EGR outlet pipe to the EGR valve inlet pipe assembly. Remove the EGR valve outlet pipe. To install, reverse removal procedure. Tighten the EGR valve outlet pipe bolt/nut to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).

Scheme 51

EVAP CANISTER

Note. Partially lowering the fuel tank, may be necessary to gain access to the EVAP canister.

Carefully lower the fuel tank. See FUEL TANK under FUEL SYSTEMS. Disconnect the EVAP vent hose, the purge pipe, and the vapor pipe from the EVAP canister. (Scheme 61) Release the canister from the retaining strap. Remove the canister from the fuel tank.

Note. Replace the retaining strap when replacing the EVAP canister.

Position the EVAP canister on the fuel tank. Secure the EVAP canister to the fuel tank with a new retaining strap. Install the EVAP vent hose, the purge pipe, and the vapor pipe to the EVAP canister. Install the fuel tank. See FUEL TANK under FUEL SYSTEMS.

Scheme 52

EVAP CANISTER PURGE SOLENOID

Note. EVAP canister purge solenoid may also be referred to as EVAP canister purge valve or EVAP canister purge solenoid valve.

Turn OFF the ignition. Disconnect the EVAP canister purge solenoid electrical connector. see scheme 62 Disconnect the EVAP canister purge pipe from the EVAP canister purge solenoid. Disconnect the vacuum supply hose from the EVAP canister purge solenoid. Remove the EVAP canister purge solenoid retaining bolt. Remove the EVAP canister purge solenoid from the intake manifold.

Position the EVAP canister purge solenoid on the intake manifold and install the retainer bolt. Tighten the EVAP canister purge solenoid retaining bolt to specification. See TORQUE SPECIFICATIONS . Connect the EVAP canister purge pipe and the vacuum supply hose. Connect the EVAP canister purge solenoid electrical connector.

Scheme 53

1. Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the EVAP canister purge solenoid harness connector. (Scheme 48)or see scheme 63.
2. Disconnect the EVAP canister purge solenoid purge pipe and vacuum supply hose. Release the retaining tab on the EVAP canister purge mounting bracket and remove the EVAP canister purge solenoid. Inspect for carbon release exiting the EVAP canister purge solenoid. See «EVAP SYSTEM CLEANING»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__evap-system-cleaning).

Install the EVAP canister purge solenoid onto the EVAP canister purge solenoid mounting bracket. Connect the EVAP canister purge valve purge pipe and vacuum supply hose. Connect the EVAP canister purge valve harness connector. Install the fuel injector sight shield.

Scheme 54

EVAP CANISTER VENT VALVE

Note. The EVAP canister vent valve may also be referred to as a EVAP canister vent solenoid or EVAP canister vent solenoid valve.

Raise and support the vehicle. Remove the left inner rear fender. Disconnect the EVAP canister vent valve electrical connector. see scheme 64 Disconnect the vent hose from the EVAP canister vent valve. Remove the EVAP canister vent valve from the bracket. To install, reverse removal procedure.

Scheme 55

EVAP SYSTEM CLEANING

Inspection Procedure

1. Turn OFF the ignition off. Remove the EVAP canister purge solenoid. See «EVAP CANISTER PURGE SOLENOID»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__evap-canister-purge-solenoid) . Lightly tap the EVAP canister purge solenoid on a hard surface.
2. Inspect for carbon particles exiting either of the vacuum ports. If no carbon particles were detected, but a blockage was detected during a diagnostic procedure, install the original EVAP canister purge valve. Continue with the cleaning procedure.
3. If carbon particles are found during the inspection procedure, continue with the cleaning procedure. If a diagnostic procedure directed you to replace the EVAP canister purge valve and no carbon particles were detected, replace the EVAP canister purge valve. Return to the diagnostic procedure that sent you here.

Cleaning Procedure

1. Raise and support vehicle. Remove the EVAP canister. See «EVAP CANISTER»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__evap-canister) . Turn off the main valve on the EVAP Pressure/Purge Diagnostic Station (J-41413).
2. Disconnect the hose from the diagnostic station pressure regulator. Using a section of vacuum hose, connect one end onto the diagnostic station pressure regulator. Connect the other end of the vacuum hose to the canister side of the purge pipe.
3. Turn on the main nitrogen cylinder valve and continue to discharge nitrogen for 15 seconds. If the nitrogen does not dislodge the carbon particles, replace the purge pipe. Return the EVAP pressure/purge diagnostic station to the stations original condition.
4. Install a new EVAP canister. Lower the vehicle. Install a new EVAP canister purge valve. Return to the diagnostic procedure that sent you here.

Removal (3.8L - Grand Prix & Regal)

1. Secondary Air Injection (AIR) pump is located under left front of vehicle. Raise and support the vehicle. Remove the left wheel assembly. Remove the fasteners from the front portion of the left front fender liner. see scheme 65
2. Reposition the splash shield to gain access to the pump and bracket assembly. Reposition the sound insulator to gain access to the pump and bracket assembly. Disconnect the pump electrical connector. Remove the pump/bracket assembly fasteners.
3. Reposition the pump and bracket assembly to gain access to the outlet hose. Remove the outlet hose from the pump. Remove the pump and bracket assembly from the vehicle.

Transfer parts as necessary. Attach the pump and bracket assembly to the frame rail using the fasteners. Tighten the fasteners to specification. See TORQUE SPECIFICATIONS . Connect the pump electrical connector. Install the outlet hose to the pump. Raise the sound insulator into position. Raise the front fender liner into position. Install the front fender liner fasteners. Install left front wheel assembly. Lower the vehicle.

Scheme 56

Removal (3.8L - Impala & Monte Carlo)

1. Secondary Air Injection (AIR) pump is located under left front of vehicle. see scheme 66 Raise and support the vehicle. Remove the left wheel assembly. Remove the left front fender liner. See «LEFT FRONT FENDER LINER»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) under MISCELLANEOUS.
2. Loosen the AIR exhaust pipe hose pinch clamp. Disconnect the AIR exhaust hose from the AIR pump. Disconnect the AIR pump electrical connector. Remove the bolts securing the AIR pump bracket to the frame. Remove the AIR pump and bracket as an assembly.

Scheme 57

1. Secure the AIR pump and bracket to the Frame mount with the nuts. Tighten the bolts securing the AIR pump mounting bracket to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications) . Connect the AIR pump electrical connector.
2. Lightly lubricate inner edge of AIR exhaust hose. Attach the AIR exhaust hose to the AIR pump outlet port. Place the AIR exhaust hose pinch clamp around the AIR pump outlet port and exhaust hose connection. Install the left front fender liner. See «LEFT FRONT FENDER LINER»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation) under MISCELLANEOUS. Install the left wheel assembly. Lower the vehicle.

1. Secondary Air Injection (AIR) pump is located under left front of vehicle. Remove the outlet hose clamp at the intermediate pipe. Remove the outlet hose from the intermediate pipe. Raise and support the vehicle. Remove the left front wheel assembly.
2. Remove the fasteners from the front portion of the left front fender liner. see scheme 65 Reposition the fender liner to gain access to the outlet hose. Remove the outlet hose from the pump. Remove the outlet hose from the vehicle.

Install the outlet hose to the vehicle. Install the outlet hose to the pump. Raise the left front fender liner into position. Install the fender liner fasteners. Lower the vehicle. Install the outlet hose to the intermediate pipe. Install the outlet hose clamp at the intermediate pipe.

SECONDARY AIR INJECTION SHUT-OFF VALVE

Turn OFF the ignition. Reposition the pinch clamp from the valve end of the hose. Disconnect the vacuum line from the valve. see scheme 67 Remove the Secondary Air Injection (AIR) pipe fasteners. Remove the fastener that secures the valve to the bracket. Remove the valve and pipe assembly from the vehicle. To install, reverse removal procedure.

Scheme 58

Turn OFF the ignition. Disconnect the vacuum hoses from the Secondary Air Injection (AIR) vacuum control solenoid. see scheme 68 Disconnect the electrical connector from the solenoid. Remove the solenoid fastener. Remove the solenoid from the vehicle. To install, reverse removal procedure.

Scheme 59

1. Raise and support the vehicle. Remove left front wheel assembly. Drill out the plastic rivets from the front fascia extension corner to front fender liner, if equipped. see scheme 69 Remove the screws from the front fender liner at the front bumper fascia. see scheme 65
2. Remove the nut from the stud at the rear of the front fender liner. Remove the bolt from the front tab of the front fender liner at the lower engine compartment side rail. see scheme 70 Remove the screws from the front fender liner. Drill out the plastic rivet from the front rocker panel to front fender liner, if equipped. Remove the front fender liner.

1. Position the fender liner to the fender, over the stud and behind the rocker molding. see scheme 65 Install the nut to the stud at the rear of the front fender liner. Tighten the front fender liner stud nut to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/impala/viii-1999-2006/remont/removal-installation/#how-to-overhaul-the-engine-controls-removal-installation__torque-specifications).
2. Install the screws to the front fender liner at the front bumper fascia. Tighten the front fender liner-to-front bumper fascia screws to specification. Install the screws to the front fender liner. see scheme 70 Tighten the front fender liner screws to specification.
3. Using a new plastic rivet, install the plastic rivet to the rocker panel and front fender liner, if equipped. Install the bolt to the front tab of the front fender liner at the lower engine compartment side rail. Tighten the front fender liner to rear of fender bolt to specification. Using new plastic rivets, install the plastic rivets to the front fascia extension corner and front fender liner. see scheme 69

Scheme 60

Scheme 61

TORQUE SPECIFICATIONS

TORQUE SPECIFICATIONS

See also:
• FASTENER NOTICE
• AIR CLEANER INTAKE DUCT
• FUEL SYSTEM PRESSURE RELEASE
• FUEL RAIL & INJECTORS
• TORQUE SPECIFICATIONS
• COOLING SYSTEM BLEEDING
• FUEL TANK DRAINING
• FUEL TANK
• THROTTLE BODY
• EGR VALVE
• EGR SYSTEM CLEANING
• REMOVAL & INSTALLATION (3.8L - OUTLET PIPE)
• EVAP SYSTEM CLEANING
• EVAP CANISTER PURGE SOLENOID
• EVAP CANISTER