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How to Overhaul & Installation the Engine Controls - Removal Buick LeSabre VIII

Removal & Installation 33 illustrations ~8527 words

INTRODUCTION

CAUTIONWhen battery and some PCM input devices are disconnected, vehicle computer and memory systems may lose memory data. Driveability problems may exist until computer systems have completed a relearn cycle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION before disconnecting battery.

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.

SUPERCHARGER

CAUTIONServicing of the supercharger unit itself is limited to replacement only. No attempt should be made to disassemble the supercharger, as parts damage may result.

Removal (VIN 1)

  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-system-pressure-release) under FUEL SYSTEMS. Remove fuel injector sight shield (upper engine cover) from engine. Remove the supercharger belt. Disconnect the vacuum brake booster hose from the vacuum connections and position aside.
  2. Remove the evaporative emission canister purge solenoid and secure the hose to the air inlet grill. See «EVAP CANISTER PURGE SOLENOID»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__evap-canister-purge-solenoid) under EMISSION SYSTEMS & SUB-SYSTEMS. Remove the fasteners securing the generator brace. Remove the generator brace.
  3. Disconnect the right side spark plug wires from the ignition module and position aside. Remove the engine wiring harness heat shield fasteners. Remove the engine wiring harness heat shield. Remove the fuel rail mounting bolts and the fuel rail with the injectors. See «FUEL RAIL & INJECTORS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-rail-injectors) under FUEL SYSTEMS.
  4. Disconnect the MAP sensor connector and hose. Remove the MAP sensor bracket and bolts. Remove the boost control solenoid. See «BOOST CONTROL SOLENOID»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) . Remove the air cleaner intake duct. Remove the nuts securing the throttle body to the supercharger.
  5. Remove the throttle body and position aside. Remove the throttle body gasket. Remove the supercharger mounting bolts. Remove the supercharger from the intake manifold. Clean and inspect the supercharger. Clean the lower intake manifold mating surface.
  1. Install the new supercharger gasket. Do not use any sealer on the gasket. Position the supercharger to the intake manifold. Install the supercharger mounting bolts. Tighten the supercharger mounting bolts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Position a new throttle body gasket to the supercharger.
  2. Install the throttle body to the supercharger. Install the nuts securing the throttle body to the supercharger. Tighten the throttle body nuts to specification. Install the air cleaner intake duct. Install the boost control solenoid. Position the MAP sensor bracket to the engine. Install the MAP sensor bracket bolts. Tighten the MAP sensor bracket bolts to specification.
  3. Connect the MAP sensor connector and hose. Install the fuel rail assembly. See «FUEL RAIL & INJECTORS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-rail-injectors) under FUEL SYSTEMS. Position the engine wiring harness heat shield to the engine. Install the engine wiring harness heat shield fasteners. Connect the right side spark plug wires to the ignition module.
  4. Install the generator brace and fasteners. Tighten the generator brace bolt/nut to specification. Install the evaporative emission canister purge valve. Connect the vacuum brake booster hose to the vacuum connections. Install the supercharger belt. Install the fuel injector sight shield.

Removal & Installation (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 1) 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 1

Scheme 1: Removal & Installation (VIN 1)
Scheme 1: Removal & Installation (VIN 1)
  1. Remove the boost control solenoid. See «BOOST CONTROL SOLENOID»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Disconnect the vacuum hose from the bypass valve actuator. (Scheme 1)
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications).

POWERTRAIN CONTROL MODULE

CAUTIONIn order to prevent possible electrostatic discharge damage to the PCM, do not touch the connector pins or soldered components on the circuit board. Service of the Powertrain Control Module (PCM) should normally consist of either replacement of the PCM or Electrically Erasable Programmable Read Only Memory (EEPROM) programming. If the diagnostic procedures call for PCM replacement, test the PCM first to see if the PCM is the correct part. If the PCM is faulty, remove the PCM and install a new service PCM. The new service PCM is not programmed. You must program the new PCM. DTC P0602 indicates the EEPROM is not programmed or has malfunctioned.
CAUTIONTurn OFF the ignition when installing or removing the PCM connectors and disconnecting or reconnecting the power to the PCM (battery cable, PCM pigtail, PCM fuse, jumper cables, etc.) in order to prevent internal PCM damage.

Removal (Bonneville & LeSabre)

  1. PCM is located inside air cleaner housing assembly. (Scheme 2) Turn OFF the ignition. Disconnect negative battery cable. Disconnect the Intake Air Temperature (IAT) sensor electrical connector.
  2. Loosen the clamp securing the air intake duct to the air cleaner housing. Carefully remove the air intake duct from the throttle body and from the air cleaner housing. Remove the 2 screws from the 2 air cleaner housing sections. Remove the air cleaner housing cover assembly.
  3. 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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Install the PCM and harness into the air cleaner housing. Install the air cleaner housing cover assembly.
  2. Reinstall the 2 screws to the 2 air cleaner housing sections. Carefully reinstall the air intake duct to the throttle body and to the air cleaner housing. Tighten the clamp securing the air intake duct to the air cleaner housing. Reconnect the negative battery cable.
  3. The new PCM must be programmed. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. The replacement PCM will not allow secondary air injection pump operation until a total of 10 miles have been accumulated.

Scheme 2

Scheme 2
Scheme 2

Removal (Park Avenue)

Turn OFF the ignition. Disconnect the negative battery cable. Remove the screws from the air cleaner top cover. Remove the air cleaner top cover. Disconnect the harness connectors from the PCM. (Scheme 3) Remove the PCM from the air cleaner housing assembly.

  1. Install the connectors to the PCM. Tighten the connectors to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Install the PCM into the air cleaner housing assembly. Install the air cleaner top cover. Connect the negative battery cable.
  2. The new PCM must be programmed. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. The replacement PCM will not allow secondary air injection pump operation until a total of 10 miles have been accumulated.

Scheme 3

Scheme 3
Scheme 3

Removal & Installation

See CAMSHAFT POSITION SENSOR under IGNITION SYSTEMS.

See CRANKSHAFT POSITION SENSOR under IGNITION SYSTEMS.

ENGINE COOLANT TEMPERATURE SENSOR

CAUTIONUse care when handling the engine coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system.

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 4) 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 (9985253) 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 4

Scheme 4: Installation
Scheme 4: Installation

See FUEL LEVEL SENSOR under FUEL SYSTEMS.

See FUEL TANK PRESSURE SENSOR under FUEL SYSTEMS.

HEATED OXYGEN SENSOR

CAUTIONThe Heated Oxygen Sensor (HO2S) uses a permanently attached pigtail and connector. Do not remove this pigtail from the HO2S. Damage or the removal of the pigtail or the connector could affect the proper operation of the sensor. Take care when handling the HO2S. Keep the in-line electrical connector and the louvered end free of grease, dirt, or other contaminants. Also avoid using cleaning solvents of any type. Do not drop the HO2S. Do not roughly handle the HO2S. The HO2S may be difficult to remove when the engine temperature is less than 120°F (48°C).

Removal (HO2S 1)

  1. Turn OFF the ignition. HO2S 1 is located in exhaust manifold. (Scheme 5) Remove fuel injector sight shield (upper engine cover) from engine. Remove the HO2S 1 retaining clip from the bracket.
  2. Disconnect the HO2S electrical connector tab from the HO2S 1 retaining clip. Remove the HO2S electrical connector retainer. Raise and support the vehicle. harness connector. Using Heated Oxygen Sensor Wrench (J-39194), remove the HO2S from the exhaust manifold.
  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 (5613695), if necessary.
  3. Install the HO2S and tighten to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Connect HO2S harness connector. Connect the electrical connector tab to the bracket. Install the HO2S electrical connector retainer. Lower vehicle. Install the fuel injector sight shield.

Scheme 5

Scheme 5
Scheme 5

Removal (HO2S 2)

Turn OFF the ignition. HO2S 2 is located behind catalytic converter. (Scheme 6) Remove fuel injector sight shield (upper engine cover) from engine. Raise and support vehicle. Remove the splash shield. Disconnect the electrical connector retaining tab from the HO2S electrical connector. Disconnect the HO2S electrical connector. Using Heated Oxygen Sensor Wrench (J-39194), 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 (5613695), if necessary.
  3. Install the HO2S and tighten to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Connect HO2S electrical connector. Connect the HO2S electrical connector retaining tab. Install the splash shield. Lower vehicle.

Scheme 6

Scheme 6
Scheme 6

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.

Removal (VIN K)

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the MAP sensor electrical connector. (Scheme 7) 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 7

Scheme 7: Installation
Scheme 7: Installation

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Manifold Absolute Pressure (MAP) sensor electrical connector. (Scheme 8) 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 8

Scheme 8: Installation
Scheme 8: Installation

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Mass Airflow (MAF) sensor electrical connector. (Scheme 9) 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 9

Scheme 9: Installation
Scheme 9: Installation

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the Throttle Position (TP) sensor electrical connector. (Scheme 9) Remove the 2 TP sensor screws. Remove the TP sensor.

Install the TP sensor. Apply Loctite® 262 Thread-Locking Compound (1052624) or equivalent to the TP sensor screws. Install the 2 TP sensor screws. Tighten the screws to 2 specification. See TORQUE SPECIFICATIONS . Connect the TP sensor electrical connector. Install the fuel injector sight shield.

COOLING SYSTEM BLEEDING

CAUTIONDo not add any engine coolant supplement sealant pellets to the cooling system. When adding coolant, it is important that you use GM Goodwrench Dex-Cool® or Havoline® DEX-COOL® coolant.

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. Fill the radiator and the coolant reservoir to the full cold line with GM Goodwrench® DEX-COOL® or Havoline® DEX-COOL® coolant. To ensure sufficient engine cooling, freezing and corrosion protection, maintain the protection level at -34°F (-37°C). Wait for two minutes and recheck the level of the coolant in the radiator.
  2. If necessary, add coolant to radiator until the coolant level is at the base of the radiator fill neck. Install the radiator pressure cap, making sure the arrows on the cap line up with the coolant recovery tube. Place the heater and A/C control in any A/C mode except Max and the temperature in the highest setting. Start the engine and allow to idle until the lower radiator-to-coolant pump hose is hot.
  3. Cycle the engine speed up to about 3000 RPM and back to idle five times. Slowly open the bleed valve on the top of the thermostat housing for approximately 15 seconds to expel any trapped air in the cooling system. Close the air bleed valve. Do not overtighten. Allow the engine to cool to outside temperature. Ensure the coolant level in the reservoir and the radiator are at the proper levels.

Remove the coolant recovery reservoir. Remove the drive belt. Disconnect the electrical connector from the Camshaft Position (CMP) sensor. (Scheme 10) 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 10

Scheme 10: Installation
Scheme 10: Installation
  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 11) DO NOT use a pry bar. Remove the CKP sensor bolts. Remove the CKP sensor.

Scheme 11

Scheme 11
Scheme 11
  1. Install the CKP sensor. Install the CKP sensor bolts. Tighten the bolts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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. Tighten wheel lug nuts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) .
  4. 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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications). Connect the spark plug wires to the ignition coils. (Scheme 12)

Scheme 12

Scheme 12
Scheme 12
  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. Remove 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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications). Connect the spark plug wires to the ignition coils. (Scheme 12)

Removal & Installation (KS 1)

WARNINGHot engine coolant may cause severe burns. Although the cooling system has been drained, coolant still remains in the engine water jacket. This coolant will drain with the removal of the Knock Sensor (KS).
  1. Turn OFF the ignition. Drain the cooling system. Raise and support the vehicle. Locate Knock Sensor (KS) to be removed. (Scheme 13) Disconnect the KS electrical connector. Remove the KS.
  2. To install, reverse removal procedure. Tighten the KS to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications). Connect the KS electrical connector. Lower the vehicle. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__cooling-system-bleeding) under COOLING SYSTEM.

Scheme 13

Scheme 13
Scheme 13

Removal & Installation (KS 2)

  1. Turn OFF the ignition switch. Raise the vehicle. Remove the bolts from the splash shield. Drain the cooling system. Remove the bolts from the KS heat shield located under the freeze plug. (Scheme 14) Disconnect the wiring harness connector from the knock sensor. Remove the KS from the engine block.
  2. To install, reverse removal procedure. Tighten the KS and KS heat shield bolts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications). Connect the KS electrical connector. Lower the vehicle. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__cooling-system-bleeding) under COOLING SYSTEM.

Scheme 14

Scheme 14
Scheme 14

Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. 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. Install fuel injector sight shield.

FUEL SYSTEMS

WARNINGAlways release fuel system pressure before disconnecting any fuel injection-related component. DO NOT allow fuel to contact engine or electrical components.

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. Remove fuel injector sight shield (upper engine cover) from engine. Remove the fuel pressure connection cap from 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.

Removal (Quick-Connect Fitting - With Metal Collar)

  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 15)
  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.
WARNINGIn order to reduce the risk of fire and personal injury, before connecting fuel pipe fittings, always apply a few drops of clean engine oil to the male pipe end. This will ensure proper reconnection and prevent a possible fuel leak. During normal operation, the "O" rings located in the female connector will swell and may prevent proper reconnection if not lubricated.

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 15

Scheme 15
Scheme 15

Removal (Quick-Connect Fitting - With Plastic Collar)

  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 16) 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.
WARNINGIn order to reduce the risk of fire and personal injury, before connecting fuel pipe fittings, always apply a few drops of clean engine oil to the male pipe end. This will ensure proper reconnection and prevent a possible fuel leak. During normal operation, the "O" rings located in the female connector will swell and may prevent proper reconnection if not lubricated.

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 16

Scheme 16
Scheme 16

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.

Note. This procedure is for removal of the fuel filler tube ONLY. In order to remove the fuel filler hose connecting the fuel filler tube to the fuel tank. Removal of the fuel tank is necessary.

  1. Drain the fuel tank below the level of the fuel filler hose. See «FUEL TANK DRAINING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank-draining). Raise and support vehicle. Open the fuel filler door and remove fuel filler cap.
  2. Remove the sealing ring from around the fuel filler tube. (Scheme 17) Raise and support the vehicle. Remove the fuel filler tube cover. Remove the bolt from the fuel filler tube ground wire.
  3. Loosen the fuel filler tube hose clamp. Remove the fuel filler tube from the fuel filler hose. If it is necessary to remove the fuel filler hose, remove the fuel tank. See «FUEL TANK»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank).
  1. Install the fuel tank if previously removed. See «FUEL TANK»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank) . Install the fuel filler tube into the fuel filler hose. Position the fuel filler tube for best fit and alignment then secure the fuel filler tube hose clamp.
  2. Tighten the hose clamp to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Install the bolt to the fuel filler tube ground wire. Tighten the bolt to specification. Install the fuel filler tube cover. Lower the vehicle. Install the sealing ring around the fuel filler tube. Add fuel to the fuel tank. Inspect for fuel leaks. Install the fuel filler cap and close the fuel filler door.

Scheme 17

Scheme 17
Scheme 17

FUEL FILTER

Note. There is not a service interval for fuel filter replacement. Only replace the fuel filter if the filter is restricted.

  1. Fuel filter is located underneath vehicle. (Scheme 18) Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Disconnect the threaded nut fitting at the outlet of the fuel filter. Drain any remaining fuel into an approved gasoline container. Remove the fuel pipe "O" ring. Remove the fuel filter.

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 new plastic connector retainer on the fuel filter inlet. Install the new retainer in the same position as on the old fuel filter. Lubricate the new fuel pipe "O" ring with clean engine oil. Install the fuel pipe "O" ring. Slide the fuel filter into place.
  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. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) .
  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. Install the fuel injector sight shield.

Scheme 18

Scheme 18
Scheme 18
  1. Remove fuel sender assembly from fuel tank. See «FUEL SENDER ASSEMBLY»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). 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 retaining clip. Squeeze the locking tabs and remove the fuel level sensor from the fuel sender assembly. (Scheme 19) To install, reverse removal procedure.

Scheme 19

Scheme 19
Scheme 19
  1. The fuel pressure regulator is located on the fuel rail. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 20) 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.
CAUTIONDo not use compressed air in order to test or clean a fuel pressure regulator as damage to the fuel pressure regulator may result. Clean the fuel pressure regulator filter screen with gasoline, if necessary. Do not immerse the fuel pressure regulator in a solvent bath in order to prevent damage to the fuel pressure regulator.
  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 20

Scheme 20
Scheme 20

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.

Removal (3.8L - VIN K)

  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) .
  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. Carefully raise the injector using Fuel Injector Remover (J-43013). 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.
WARNINGIn order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector "O" rings in the proper position. If the upper and lower "O" rings are different colors (Black and Brown), be sure to install the Black "O" ring in the upper position and the Brown "O" ring in the lower position on the fuel injector. The "O" rings are the same size but are made of different materials.
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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.

Removal (3.8L - VIN 1)

  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) .
  2. Disconnect the vacuum line from the fuel pressure regulator. Remove the ignition coil wires from the retainer clips on top of the supercharger. Remove the rear generator mounting bracket with the EVAP canister purge solenoid valve attached.
  3. Remove the bypass valve actuator. See «BYPASS VALVE ACTUATOR»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) under AIR INDUCTION SYSTEMS. Disconnect the fuel injector electrical connectors. Remove the fuel injector electrical harness clips holding harness to front of the fuel rail. Remove the fuel rail hold-down nuts. Remove the fuel rail with equal force on both sides of the fuel rail.
  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.
WARNINGIn order to reduce the risk of fire and personal injury that may result from a fuel leak, always install the fuel injector "O" rings in the proper position. If the upper and lower "O" rings are different colors (Black and Brown), be sure to install the Black "O" ring in the upper position and the Brown "O" ring in the lower position on the fuel injector. The "O" rings are the same size but are made of different materials.
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications).
  3. Install the fuel injector electrical harness clips holding harness to the front of fuel rail. Connect the 6 fuel injector electrical connectors. Install the bypass valve actuator. (Scheme 1) Install the rear generator mounting bracket with the EVAP canister purge solenoid valve. Install the ignition coil wires to the retainer clips to the top of supercharger. Connect the vacuum line to the fuel pressure regulator.
  4. 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.
  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-system-pressure-release). Drain the fuel tank. See «FUEL TANK DRAINING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank-draining).
  2. Remove the rear compartment floor trim. Remove the fuel sender access panel bolts. (Scheme 21) Remove the fuel sender access panel. Disconnect the fuel sender quick-connect fittings. See «FUEL LINE DISCONNECT FITTINGS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Disconnect the fuel sender electrical connector. Disconnect the Fuel Tank Pressure (FTP) sensor electrical connector.
  3. Remove the fuel sender retaining ring using Fuel Sender Lock Nut Wrench (J-39765). Do Not handle the fuel sender assembly by the fuel pipes. The amount of leverage generated by handling the fuel pipes could damage the joints. When removing the fuel sender assembly from the fuel tank, the reservoir bucket on the fuel sender is full of fuel.
  4. The fuel sender must be tipped slightly during removal in order to avoid damage to the float. Place any remaining fuel into an approved container once the fuel sender is removed from the fuel tank. Remove the fuel sender assembly. Clean the fuel sender sealing surfaces. 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. Install the fuel sender assembly and the fuel sender lock ring using Fuel Sender Lock Nut Wrench (J-39765).
  2. Connect the quick-connect fittings at the fuel sender. Connect the fuel sender electrical connector. Connect the FTP sensor electrical connector. Add fuel to the fuel tank. Install the fuel tank filler pipe cap. Connect the negative battery cable.
  3. 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 sender access panel. Install the fuel sender access panel bolts.
  4. Tighten the fuel sender access panel bolts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Install the rear compartment floor trim. Install the fuel injector sight shield.

Scheme 21

Scheme 21
Scheme 21

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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-system-pressure-release) . Remove the fuel tank. See «FUEL TANK»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank) . Remove the fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) .
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) . Install the fuel tank. See «FUEL TANK»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank) .

FUEL TANK

CAUTIONDo not attempt to straighten any kinked nylon fuel lines. Replace any kinked nylon fuel feed or return pipes in order to prevent damage to the vehicle. Do not attempt to repair sections of nylon fuel pipes. If the nylon fuel pipes are damaged, replace the pipes.
  1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-system-pressure-release). Drain the fuel tank. See «FUEL TANK DRAINING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__fuel-tank-draining). Raise and support vehicle.
  2. Remove the filler pipe opening cover. (Scheme 17) Disconnect the fuel fill hose from the fuel fill pipe. Remove the rear suspension support assembly. See appropriate REAR article in SUSPENSION.
  3. Disconnect the fuel feed pipe and the fuel return pipe. See «FUEL LINE DISCONNECT FITTINGS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Disconnect the evaporative emission pipe from the EVAP canister.
  4. Remove the fuel and EVAP retainer from the frame. Disconnect the fuel sender electrical connector. Disconnect the fuel sender electrical harness from the retainers. Support the fuel tank. Remove the fuel tank strap bolts. Remove the fuel tank.
  1. Position and support the fuel tank with the aid of an assistant. Install the fuel tank straps. Install the fuel tank strap bolts. Tighten the fuel tank strap bolts to «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) . Connect the fuel sender electrical connector.
  2. Install the fuel sender electrical harness into the retainers. Install the fuel and EVAP retainer to the frame. Connect the EVAP pipe to the EVAP canister. Connect the fuel feed pipe and the fuel return pipe. Install the rear suspension support assembly. See appropriate REAR article in SUSPENSION. Connect the fuel filler hose to the fuel filler pipe. Tighten the clamp to specification.
  3. Install the filler pipe opening cover. Lower the vehicle. Add fuel to the fuel tank. Install the fuel tank filler pipe cap. Connect the negative battery cable. Perform the following procedure in order to inspect for leaks. Turn ON the ignition switch for 2 seconds. Turn OFF the ignition switch for 10 seconds. Turn ON the ignition switch. Inspect for fuel leaks. Install the fuel injector sight shield.

FUEL TANK DRAINING

WARNINGGasoline or gasoline vapors are highly flammable. A fire could occur if an ignition source is present. Never drain or store gasoline in an open container, due to the possibility of fire or explosion. Drain the fuel tank to at least 3/4 of a tank before removing the fuel sender retaining ring or fuel sender access panel in order to avoid possible fuel spillage. Failing to follow this procedure could result in personal injury. Have a dry chemical (Class B) fire extinguisher nearby.
CAUTIONDrain the fuel tank with a hose which has a 0.5" (13 mm) or smaller diameter in order to prevent the drain hose from getting stuck inside the fuel tank filler neck pipe check valve. Damage to the check valve may result.

Turn OFF the ignition. Disconnect the negative battery cable. Remove the fuel tank filler pipe cap. Use a hand-operated fuel pump device in order to drain the fuel through the fuel tank filler pipe. Install the fuel tank filler pipe cap. Connect the negative battery cable.

Remove the rear compartment floor trim. Remove the fuel sender access panel bolts. (Scheme 21) Remove the fuel sender access panel. Disconnect the Fuel Tank Pressure (FTP) sensor electrical connector. Remove the FTP sensor.

Install the FTP sensor. Connect the FTP sensor electrical connector. Install the fuel sender access panel. Install the fuel sender access panel bolts. Tighten the fuel sender access panel bolts to specification. See TORQUE SPECIFICATIONS . Install the rear compartment floor trim.

Turn OFF the ignition Remove fuel injector sight shield (upper engine cover) from engine. Remove the electrical connector from the Idle Air Control (IAC) valve. (Scheme 9) Remove the 2 IAC valve retaining screws. Remove the IAC valve from the throttle body. Remove the IAC valve "O" ring from the IAC valve. Inspect the "O" ring for cracks or damage. Replace the "O" ring if necessary.

CAUTIONThe IAC valve may be damaged if installed with the cone (pintle) extended more than 1.10" (28 mm). Measure the distance that the valve is extended before installing a new valve. The distance from the idle air control valve motor housing to the end of the idle air control valve pintle should be less than 1.10" (28 mm). Manually compress the pintle until the extension is less than 1.10" (28 mm).
  1. Measure the distance between the tip of the IAC valve pintle and the mounting surface. (Scheme 22) 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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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. Install the fuel injector sight shield.

Scheme 22

Scheme 22
Scheme 22

THROTTLE BODY

CAUTIONDo not use solvent of any type when cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as damage to the gasket surfaces and throttle body assembly may result. Use care in cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as sharp tools may damage the gasket surfaces.
  1. Remove fuel injector sight shield (upper engine cover) from engine. Drain the cooling system. Disconnect the Intake Air Temperature (IAT) sensor electrical connector. Remove the intake air duct from the throttle body. Disconnect the Idle Air Control (IAC) valve electrical connector. (Scheme 9) Disconnect the Throttle Position (TP) sensor electrical connector.
  2. Disconnect the Mass Airflow (MAF) sensor electrical connector. Remove the accelerator control cable from the throttle body lever. Remove the accelerator control cable from the accelerator controls bracket. Remove the cruise control cable from the accelerator controls bracket. Disconnect the electrical harness retainer clip from the accelerator controls cable bracket. Remove the vacuum hoses from the throttle body.
  3. Remove the secondary air injection reaction pump outlet pipe, if applicable. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) under EMISSION SYSTEMS & SUB-SYSTEMS. Remove the throttle body support bracket bolts. Remove the throttle body support bracket. Remove the throttle body nuts. Remove the throttle body assembly.
  4. Clean the throttle body gasket mating surfaces. If throttle body is being replaced, remove the accelerator controls bracket from the throttle body.
CAUTIONDo not use solvent of any type when cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as damage to the gasket surfaces and throttle body assembly may result. Use care in cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as sharp tools may damage the gasket surfaces.
  1. Install the accelerator control bracket to the throttle body, if necessary. Install the new gasket. Install the throttle body assembly. Install the throttle body nuts. Tighten the nuts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 outlet pipe, if applicable. Install the vacuum hoses to throttle body. Install the electrical harness retainer clip to the accelerator control cable bracket, if previously removed. Install the accelerator control cable to the accelerator control bracket and throttle body lever. Install the cruise control cable to the accelerator control bracket and throttle body lever.
  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. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__cooling-system-bleeding) under COOLING SYSTEM. Install the fuel injection sight shield.
  1. Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Drain the cooling system. Disconnect the Intake Air Temperature (IAT) sensor electrical connector. Remove the air cleaner intake duct from the throttle body. Disconnect the Idle Air Control (IAC) valve electrical connector. (Scheme 9) Disconnect the Mass Airflow (MAF) sensor electrical connector.
  2. Disconnect the Throttle Position (TP) sensor electrical connector. Remove the cruise control cable from the accelerator control bracket and throttle body lever. Remove the accelerator control cable from the accelerator control bracket and throttle body lever. Remove the electrical harness retainer clip from the accelerator control cable bracket, if applicable. Note locations and remove the vacuum hoses from the throttle body.
  3. Remove the secondary air injection reaction pump outlet pipe, if applicable. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) under EMISSION SYSTEMS & SUB-SYSTEMS. Remove the 3 nuts and bolts holding the throttle body to the supercharger. Remove the throttle body assembly from the intake manifold. Clean the gasket surface on the intake manifold and the throttle body assembly.
CAUTIONDo not use solvent of any type when cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as damage to the gasket surfaces and throttle body assembly may result. Use care in cleaning the gasket surfaces on the intake manifold and the throttle body assembly, as sharp tools may damage the gasket surfaces.
  1. Install the accelerator controls bracket to the throttle body, if necessary. Install the new gasket. Install the throttle body assembly. Install the throttle body nuts and bolts. Tighten the nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) .
  2. Install the secondary air injection reaction pump outlet pipe, if previously removed. Install the vacuum hoses to throttle body as noted on removal. Install the electrical harness retainer clip to the accelerator control cable bracket, if previously removed. Install the accelerator control cable to the accelerator control bracket and throttle body lever.
  3. Install the cruise control cable to the accelerator control bracket and throttle body lever. Connect the MAF sensor electrical connector. Connect the TP sensor electrical connector. Connect the IAC valve electrical connector. Install the air cleaner intake duct. Fill the cooling system. See «COOLING SYSTEM BLEEDING»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__cooling-system-bleeding) under COOLING SYSTEM. Install the fuel injection sight shield.

THROTTLE BODY CLEANING PROCEDURE

CAUTIONDo not subject a throttle body assembly which contains the following components to an immersion cleaner or a strong solvent: Throttle Position (TP) sensor, Idle Air Control (IAC) valve, sealed throttle shaft bearings The cleaners will damage the electric components or sensors. The cleaners will damage some of these components that contain seals or "O" rings. Solvents can wash away or break down the grease used on non-serviceable throttle shaft bearings. Never use a wire brush or scraper to clean the throttle body. A wire brush or sharp tools may damage the throttle body components. Do not use a cleaner that contains methyl ethyl ketone. This extremely strong solvent may damage components and is not necessary for this type of cleaning.
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__egr-valve-inlet-pipe) .
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 electrical connector from the Exhaust Gas Recirculation (EGR) valve. (Scheme 23) 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 23

Scheme 23: Installation
Scheme 23: Installation

EGR VALVE INLET PIPE

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

  1. Remove the Exhaust Gas Recirculation (EGR) valve. See «EGR VALVE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__egr-valve). If applicable, remove the Secondary Air Injection (AIR) pump outlet pipe. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal).
  2. Remove the EGR valve outlet pipe. See «EGR VALVE OUTLET PIPE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Remove the EGR valve inlet pipe mounting bolt from the exhaust manifold. (Scheme 24) Remove the mounting bolt and the stud from the EGR valve inlet pipe bracket. Remove the EGR valve inlet pipe assembly.

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 . Install the EGR valve inlet pipe bolt to the exhaust manifold. Tighten the bolt to specification. Install the EGR valve outlet pipe. Install the AIR pump outlet pipe, if applicable. Install the EGR valve.

Scheme 24

Scheme 24: Installation
Scheme 24: Installation
  1. If applicable, remove the Secondary Air Injection (AIR) pump outlet pipe. See «SECONDARY AIR INJECTION PUMP OUTLET PIPE/HOSE»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal). Remove the mounting bolt that attaches the Exhaust Gas Recirculation (EGR) outlet pipe flange to the intake manifold. (Scheme 25)
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications).

Scheme 25

Scheme 25
Scheme 25

The EVAP canister is located underneath rear of vehicle. (Scheme 26) Raise and support vehicle. Note location and disconnect hoses from EVAP canister. Remove EVAP canister bracket attaching nuts. Remove the EVAP canister bracket and canister. To install, reverse removal procedure. Tighten nuts to specification. See TORQUE SPECIFICATIONS.

Scheme 26

Scheme 26: Removal & Installation
Scheme 26: Removal & Installation

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.

  1. Turn OFF the ignition. Remove fuel injector sight shield (upper engine cover) from engine. Disconnect the EVAP canister purge solenoid harness connector. (Scheme 27)or (Scheme 28).
  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»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 27

Scheme 27: Installation
Scheme 27: Installation

Scheme 28

Scheme 28
Scheme 28

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. Disconnect the EVAP canister vent valve electrical connector. (Scheme 29) Disconnect the vent hose from the EVAP canister vent valve. Remove the EVAP canister vent valve bolt. Remove the EVAP canister vent valve from the vehicle. To install, reverse removal procedure.

Scheme 29

Scheme 29: Removal & Installation
Scheme 29: Removal & Installation

EVAP SYSTEM CLEANING

CAUTIONUse the EVAP Pressure/Purge Diagnostic Station (J-41413) in order to provide a clean, dry, low pressure gas source. Do not substitute any other pressurized gas source. Damage may result to the EVAP system. Proceed with the following procedure only if referenced by an EVAP diagnostic or repair procedure.

Inspection Procedure

  1. Turn OFF the ignition off. Remove the EVAP canister purge solenoid. See «EVAP CANISTER PURGE SOLENOID»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__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 solenoid. Return to the diagnostic procedure that sent you here.

Cleaning Procedure

  1. Raise and support vehicle. Remove the EVAP canister. See «EVAP CANISTER»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal) . 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.

Loosen the pinch clamp on the Secondary Air Injection (AIR) outlet pipe hose. (Scheme 30) Disconnect the AIR outlet hose from the AIR pump. Disconnect the AIR pump electrical connector. Remove the 3 nuts securing the AIR pump bracket to the transmission mount. Remove the AIR pump and the bracket as an assembly.

Secure the AIR pump and the bracket to the transmission mount with the 3 nuts. Tighten the nuts to specification. See TORQUE SPECIFICATIONS . Connect the AIR pump electrical connector. Lightly lubricate the inner edge of the AIR pump outlet hose. Attach the AIR outlet hose to the AIR pump outlet port. Place the pinch clamp around the AIR pump outlet port and outlet hose connection.

Scheme 30

Scheme 30: Installation
Scheme 30: Installation
  1. Secondary Air Injection (AIR) pump is located under front of vehicle. (Scheme 30) Remove the outlet hose clamp at the intermediate pipe. Remove the outlet hose from the intermediate pipe. Remove the outlet hose from the vehicle. Remove the throttle body support bracket fasteners.
  2. Remove the throttle body support bracket from the vehicle. Remove the AIR outlet pipe retaining nut. Remove the AIR outlet pipe hose clamp from the AIR shut-off valve. (Scheme 31) Disconnect the AIR outlet pipe hose from the AIR shut-off valve. Remove the outlet pipe from the vehicle.
  1. Install the AIR pump outlet pipe to the vehicle. Connect the AIR outlet pipe hose to the AIR shut-off valve. Install the AIR outlet pipe hose clamp to the AIR shut-off valve. Install the AIR outlet pipe retaining nut. Tighten the nut to specification. See «TORQUE SPECIFICATIONS»(/buick/lesabre/viii-2000-2005/remont/removal-installation/#how-to-overhaul-installation-the-engine-controls-removal__torque-specifications) .
  2. Install the throttle body support bracket to the vehicle. Install the throttle body support bracket fasteners. Tighten the fasteners to specification. Install the AIR outlet hose to the vehicle. Connect the outlet hose to the intermediate pipe and AIR pump. Install the outlet hose clamps to the intermediate pipe and AIR pump.

Scheme 31

Scheme 31
Scheme 31

SECONDARY AIR INJECTION SHUT-OFF VALVE

WARNINGAllow the engine to cool before servicing the Secondary Air Injection (AIR) system in order to reduce the chance of severe burns.
  1. Turn OFF the ignition. Disconnect the vacuum hose from the AIR shut-off valve. (Scheme 31) Loosen and lower the pinch clamp on the AIR pump outlet hose.
  2. Remove the 2 bolts that attach the AIR shut-off valve outlet pipe to the AIR manifold. (Scheme 32) Remove the mounting bolt that secures the shut-off valve to the bracket. Remove the AIR shut-off valve and the AIR shut-off valve outlet pipe as an assembly. To install, reverse removal procedure.

Scheme 32

Scheme 32
Scheme 32

Removal & Installation (3.8L)

Turn OFF the ignition. Disconnect the vacuum hoses from the Secondary Air Injection (AIR) vacuum control solenoid. (Scheme 33) Disconnect the electrical connector from the solenoid. Remove the solenoid fastener. Remove the solenoid from the vehicle. To install, reverse removal procedure.

Scheme 33

Scheme 33: Removal & Installation (3.8L)
Scheme 33: Removal & Installation (3.8L)

TORQUE SPECIFICATIONS

ApplicationFt. Lbs. (N.m)
AIR Pump Mounting Bracket Nuts37 (50)
Bypass Valve Actuator Bolts (VIN 1)18 (25)
Crankshaft Balancer Bolt(1) 111 (150)
Crankshaft Position Sensor Bolts22 (30)
EGR Valve Adapter Pipe-To-Exhaust Manifold Bolt21 (29)
EGR Valve Bolts/Nuts22 (30)
EGR Valve Inlet Pipe Bolt/Stud37 (50)
EGR Valve Outlet Pipe Bolt/Nut21 (29)
Engine Coolant Temperature Sensor15 (20)
Fuel Filter Outlet Pipe Fitting22 (30)
Fuel Tank Strap Bolts31 (42)
Generator Brace (VIN 1)
Bolt22 (30)
Nut37 (50)
Heated Oxygen Sensor31 (42)
Knock Sensor14 (19)
Knock Sensor Heat Shield Bolt44 (60)
MAP Sensor Bracket Bolts (VIN1)22 (30)
Spark Plug11 (15)
Supercharger Bolts (VIN 1)17 (23)
Wheel Lug Nuts100 (140)
INCH Lbs. (N.m)
AIR Pump Outlet Pipe Nut89 (10.0)
AIR Shut-Off Valve Bolt80 (9.0)
Boost Control Solenoid Nut (VIN 1)89 (10.0)
Camshaft Position Sensor89 (10.0)
EVAP Canister Bracket Nuts53 (6.0)
Fuel Filler Tube Ground Wire Bolt80 (9.0)
Fuel Filler Pipe Hose Clamp31 (3.5)
Fuel Rail Bolt/Nut89 (10.0)
Fuel Sender Access Panel Bolts18 (2.0)
Idle Air Control Valve27 (3.0)
Ignition Coil Screws40 (4.5)
Intake Air Duct Clamp18 (2.0)
Manifold Absolute Pressure Sensor Screws (VIN 1)44 (5.0)
MAF Sensor Screw27 (3.0)
PCM Connector Screws71 (8.0)
Throttle Body Nuts89 (10.0)
Throttle Body Support Bracket Nuts89 (10.0)
Throttle Position Sensor Screws18 (2.0)
(1) Tighten bolt an additional 76 degrees.
(1)Tighten bolt an additional 76 degrees.

TORQUE SPECIFICATIONS