Engine Controls - Removal & Installation - Gasoline Chevrolet Chevy Express H2500

Removal (4.3L - Upper Intake Manifold)

Note. It is not necessary to remove the upper intake manifold in order to remove the intake manifold assembly.

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Remove the engine cover. Disconnect the PCV tube from the air cleaner outlet duct. (Scheme 1)
2. Remove the retaining nut (1) from the air cleaner outlet. (Scheme 2) Remove the air cleaner outlet duct (2) from the throttle body assembly.
3. Disconnect the accelerator control cable from the throttle shaft and the accelerator control cable bracket. Disconnect the cruise control cable (if equipped) from the throttle shaft and the accelerator control cable bracket.
4. Remove the PCV valve hose assembly from the intake manifold and the valve rocker arm cover. (Scheme 3)
5. Disconnect the fuel meter body assembly connector (1), EVAP canister purge solenoid valve (2) connector, Manifold Absolute Pressure (MAP) sensor (3) connector, Throttle Position (TP) sensor (4) connector, Idle Air Control (IAC) motor (5) connector, Engine Coolant Temperature (ECT) gauge sensor (6) connector and A/C high pressure switch connector (7), if equipped. (Scheme 4)
6. Remove the engine wiring harness bracket from the intake manifold stud. (Scheme 5) Move and secure the engine wiring harness out of the way.
7. Disconnect the A/C vacuum hose from the intake manifold. (Scheme 6) Remove the power brake booster vacuum hose bracket and nut from the intake manifold stud.
8. Disconnect the power brake booster vacuum hose from the intake manifold. Remove the accelerator control cable bracket from the throttle body and the intake manifold. (Scheme 7)
9. Remove the EVAP canister purge solenoid. See «EVAP CANISTER PURGE VALVE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) under MOTORS, RELAYS & SOLENOIDS.
10. Remove the fuel lines from the fuel meter body assembly. Remove the distributor cap. See «DISTRIBUTOR»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__distributor) under IGNITION SYSTEMS. Remove the ignition control module. See «IGNITION CONTROL MODULE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) under IGNITION SYSTEMS.
11. Remove the studs for the upper intake manifold. (Scheme 8) Remove the upper intake manifold.
12. Remove the upper intake manifold gasket from the groove. Discard the gasket. Remove the seal from the fuel meter body assembly. (Scheme 9) Discard the seal.

Scheme 1

Scheme 2

Scheme 3

Scheme 4

Scheme 5

Scheme 6

Scheme 7

Scheme 8

Scheme 9

Scheme 10

Scheme 11

1. Inspect the upper intake manifold for cracks or other damage to the exterior, cracking or damage to the gasket grooves, loose or damaged bolt hole thread inserts.
2. If replacing the upper intake manifold, remove the MAP sensor and remove the throttle body. See «THROTTLE BODY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Remove the power brake booster vacuum tube fitting and the PCV valve cover from the upper intake manifold. (Scheme 10)and (Scheme 11). Remove and discard the seals.
3. If replacing the upper intake manifold, install all components removed from upper intake manifold, using NEW seals lubricated with clean engine oil as necessary.
4. Install a NEW upper intake manifold to lower intake manifold gasket in the groove of the upper intake manifold. Install the upper intake manifold onto the lower intake manifold.
5. If reusing the fasteners, apply Threadlock (GM 12345382) to the threads of the upper intake manifold attaching bolts. Install the upper intake manifold attaching studs. Install the fuel lines to the fuel meter body assembly. To complete installation, reverse removal procedure. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Install the engine cover.

Removal (4.3L - Lower)

Note. It is not necessary to remove the upper intake manifold in order to remove the lower intake manifold assembly.

Note. The following removal procedure is without the upper intake manifold removed. If it is necessary to remove or replace upper intake manifold, see REMOVAL (4.3L - UPPER INTAKE MANIFOLD) .

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Disconnect the battery negative cable. Remove the engine cover. Drain the cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) under COOLING SYSTEM.
2. Remove the retaining nut from the air cleaner outlet. Remove the air cleaner outlet duct from the throttle body assembly. Disconnect the harness connector of the Intake Air Temperature (IAT) sensor.
3. Disconnect the A/C compressor (1), the Exhaust Gas Recirculation (EGR) connector (2) and the ECT sensor (3). Remove the ground wire (4) from the stud at the water outlet. (Scheme 12)
4. Remove the radiator inlet hose at the water outlet. (Scheme 13) Remove the heater hose from the intake manifold. Remove the water pump inlet hose from the intake manifold.
5. Remove the accelerator control cable bracket from the throttle body and the intake manifold. (Scheme 7)
6. Remove the distributor. See «DISTRIBUTOR»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__distributor) under IGNITION SYSTEMS. Remove the spark plug wire harness retainer from the EGR valve inlet valve.
7. In order to remove the front intake manifold bolt, perform the following: Remove the auxiliary evaporator tube from the A/C compressor (if equipped). Remove the drive belt. Loosen the nut for the power steering pump rear bracket. Remove the bolts and the nut for the power steering pump mounting bracket. (Scheme 14) Leave the A/C compressor (if equipped), and the power steering pump on the bracket. Slide the power steering pump bracket forward to access the bolt at the front of the intake manifold.
8. Remove the Engine Coolant Temperature (ECT) sensor wire connector (if equipped) from the engine wiring harness bracket. Remove the lower intake manifold bolts. Remove the intake manifold assembly. Remove and discard the lower intake manifold gaskets.

Scheme 12

Scheme 13

Scheme 14

1. Clean all sealing surfaces and the intake manifold. If the intake manifold requires replacement see appropriate article in ENGINES.
2. Apply a 0.157" (4.0 mm) patch of Adhesive (GM 12346141) to the cylinder head side of the lower intake manifold gasket at each end. (Scheme 15) The lower intake manifold must be installed and the fasteners tightened while the adhesive is still wet to the touch.
3. Install the lower intake manifold gasket onto the cylinder head. Use the gasket locator pins in order to properly seat the lower intake manifold gasket on the cylinder head.
4. Apply a 0.197" (5 mm) bead of Adhesive (GM 12346141) to the front top of the engine block. Extend the adhesive bead 0.50" (13 mm) onto each lower intake manifold gasket. Apply a 0.197" (5 mm) bead of Adhesive (GM 12346141) to the rear top of the engine block. Extend the adhesive bead 0.50" (13 mm) onto each lower intake manifold gasket.
5. Install the lower intake manifold onto the engine block. If reusing the fasteners, apply Threadlock (GM 12345382) to the threads of the lower intake manifold bolts. Install the lower intake manifold bolts. (Scheme 16)
6. To complete installation, reverse removal procedure. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Install the engine cover.

Scheme 15

Scheme 16

Removal (4.8L, 5.3L & 6.0L)

Note. The intake manifold, throttle body, fuel injection rail, and fuel injectors may be removed as an assembly. If not servicing the individual components, remove the manifold as a complete assembly.

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Remove the throttle body. See «THROTTLE BODY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Remove the oil fill tube. Remove the fuel injectors. See «FUEL RAIL & INJECTORS (SFI)»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-rail-injectors).
2. Disconnect the following electrical connectors: Manifold Absolute Pressure (MAP) sensor (1), knock sensor (2), Exhaust Gas Recirculation (EGR) valve if equipped. (Scheme 17) Remove the knock sensor harness electrical connector from the intake manifold. Set the electrical harness aside.
3. If equipped, remove the following EGR pipe bolts: Intake manifold (1), cylinder head (2) and exhaust manifold (3). (Scheme 18) Remove the EGR pipe (with valve) and remove the EGR pipe gasket from the exhaust manifold.
4. Remove the positive crankcase ventilation (PCV) hose (with valve). (Scheme 19) Remove the MAP sensor (1) from the intake manifold. (Scheme 20)
5. Remove the accelerator control cable bracket bolts (1). Remove the accelerator control cable bracket (2) from the intake manifold. (Scheme 21)
6. Remove the evaporative emission (EVAP) purge solenoid vent tube by performing the following: Remove the EVAP tube end (1) from the solenoid (2). (Scheme 22) Squeeze the EVAP pipe quick connect fitting (3) retainer together. Remove the EVAP tube end (3) from the vapor pipe.
7. Remove the EVAP purge solenoid bolt (1), solenoid (2), and isolator (3) from the intake manifold. (Scheme 23)
8. Remove the intake manifold bolts. (Scheme 24) Remove the intake manifold. Remove the intake manifold gaskets (1) from the intake manifold. (Scheme 25) Discard the old intake manifold gaskets. Clean the gasket surfaces of the EGR pipe and the exhaust manifold, if equipped.

Scheme 17

Scheme 18

Scheme 19

Scheme 20

Scheme 21

Scheme 22

Scheme 23

Scheme 24

Scheme 25

1. Instal NEW intake manifold gaskets. Install intake manifold. Apply a 0.20" (5 mm) band of Threadlock (GM P/N 12345382) to the threads of the intake manifold bolts. Install the intake manifold bolts. Tighten bolts in sequence to specification. (Scheme 26)
2. To install, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 26

Removal & Installation (4.3L)

1. Disconnect negative battery cable. Remove engine cover. Remove air cleaner outlet duct. Remove air cleaner adapter stud. (Scheme 27)
2. Disconnect accelerator and cruise control cables. Remove accelerator cable bracket bolts and bracket. Disconnect IAC valve and TP sensor harness connectors from throttle body. (Scheme 28)and (Scheme 29).
3. Remove throttle body retaining studs. (Scheme 30) Remove throttle body assembly from intake manifold. Remove flange gasket and discard. (Scheme 31)
4. Clean gasket surface on intake manifold and throttle body. Install NEW flange gasket. Install throttle body assembly. Install throttle body studs and tighten to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Install air cleaner adapter stud.
5. To complete installation, reverse removal procedure. Before starting vehicle, ensure throttle and cruise control linkage does not hold throttle open.

Scheme 27

Scheme 28

Scheme 29

Scheme 30

Scheme 31

Removal & Installation (4.8L, 5.3L & 6.0L)

1. Remove the air cleaner assembly. Disconnect the accelerator control cable and the cruise control cable from the throttle body. (Scheme 32) Disconnect the vacuum hose from the throttle body.
2. Disconnect the Throttle Position (TP) sensor and Idle Air Control (IAC) valve harness connectors. (Scheme 33)
3. Disconnect the coolant hose from the throttle body. (Scheme 34) Disconnect the coolant hose from the vapor vent pipe. (Scheme 35)
4. Remove the throttle body attaching nuts. (Scheme 36) Remove the throttle body and the gasket. Discard the gasket.
5. Install the throttle body with a NEW gasket. To complete installation, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).
6. With the engine off, verify that the accelerator pedal moves freely. Depress the accelerator pedal to the floor and release the pedal. In order to reset the IAC valve, turn the ignition no for 10 seconds. Turn off the ignition for 5 seconds. Start the engine and check for the proper idle speed.

Scheme 32

Scheme 33

Scheme 34

Scheme 35

Scheme 36

COMPUTERIZED ENGINE CONTROLS

Note. All vehicles are equipped with either a Powertrain Control Module (PCM) or Vehicle Control Module (VCM) for engine control. Unless specifically stated, references to PCM also apply to VCM equipped vehicles. Bi-fuel vehicles are also equipped with an Fuel Injection Control Module (FICM). For FICM procedures, see FUEL INJECTION CONTROL MODULE under COMPUTERIZED ENGINE CONTROLS in CHEVY EXPRESS & SAVANA - BI-FUEL article.

Note. Some vehicles equipped with an electronically-controlled transmission also use a Transmission Control Module (TCM) for transmission control.

POWERTRAIN CONTROL MODULE

Note. Before replacing PCM, carefully inspect all wiring and control components. Failure to test for short circuits may result in repeated PCM failure due to shorts and Quad-Driver failure. To prevent internal damage to PCM, ensure ignition switch is in OFF position when connecting or disconnecting PCM harness connectors or any electrical components.

Ensure ignition is off. Disconnect negative battery cable. Remove air cleaner. Disconnect harness connectors from PCM. Remove PCM from vehicle.

Install PCM into vehicle. Connect harness connectors to PCM. Install air cleaner. Reconnect negative battery cable. If NEW PCM has been installed, PCM MUST be programmed. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

ELECTRICALLY ERASABLE PROGRAMMABLE READ-ONLY MEMORY

The Electrically Erasable Programmable Read-Only Memory (EEPROM) is a permanent memory that is part of PCM. EEPROM cannot be replaced. EEPROM contains program and calibration information that PCM uses to control powertrain. If PCM is replaced, ensure NEW PCM software/calibration is correct and most recent version for vehicle. EEPROM must be programmed when NEW PCM is installed. Program EEPROM using latest software for that specific vehicle. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION.

Note. Service of the PCM should normally consist of either replacement of the PCM or EEPROM programming. If the diagnostic procedures call for the PCM to be replaced, the PCM should be checked first to see if it is the correct part. If it is, remove the faulty PCM and install the new service PCM. The service PCM EEPROM will not be programmed. DTC P0601 and P0602 indicates the EEPROM is not programmed or has malfunctioned.

Note. Programing Powertrain Control Module requires a compatible scan tool and a Techline® terminal. Procedure uses a Tech 2® scan tool.

Remote Programming

Note. DO NOT program a control module unless you are directed by a service procedure or you are directed by a technical service bulletin. Programming a control module at any other time will not permanently correct a customer's concern.

1. Turn OFF the ignition.
2. Install the Tech 2® to the Data Link Connector (DLC), with the Tech 2® turned OFF.
3. Turn ON Tech 2®. Press ENTER at title screen.
4. Turn ON the ignition, with the engine OFF.
5. Turn OFF all vehicle accessories.
6. Select SERVICE PROGRAMMING SYSTEM at the MAIN MENU.
7. Select REQUEST INFO.
8. Enter the vehicle description by following the on-screen instructions.
9. Verify that the correct VIN is entered on the Tech 2® and select YES.
10. Turn OFF the Tech 2®.
11. Disconnect the Tech 2® from the vehicle.
12. Turn OFF the ignition.
13. Connect the Tech 2® to the terminal.
14. Launch the TIS application at the terminal.
15. Select the SERVICE PROGRAMMING SYSTEM at the main screen.
16. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select Tech 2®. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select vehicle.
17. Select NEXT.
18. Verify the connections and select NEXT.
19. Verify the VIN and select NEXT.
20. Select the appropriate controller for the vehicle being serviced.
21. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
22. Select NEXT.
23. Select the appropriate calibration file for the vehicle being serviced.
24. Select NEXT.
25. Verify your selection on the Summary screen.
26. Select NEXT.
27. Perform the CRANKSHAFT POSITION VARIATION RELEARN PROCEDURE using the SPECIAL FUNCTIONS feature, if applicable.
28. Close the application and return to the TIS APPLICATION SELECTION screen after the download is complete.
29. Turn OFF the Tech 2®.
30. Disconnect the Tech 2® from the terminal.
31. Connect the Tech 2® to the vehicle DLC, with the engine and the Tech 2® OFF.
32. Turn ON the Tech 2®.
33. Press ENTER at the TITLE screen.
34. Turn ON the ignition, with the engine OFF.
35. Select SERVICE PROGRAMMING SYSTEM.
36. Select the PROGRAM ECU function on the Tech 2®.
37. Verify the VIN and calibration numbers, select CONTINUE.
38. Follow the on-screen instructions and select CONTINUE.
39. Select CONTINUE and exit the program after the Tech 2® displays PROGRAMMING WAS SUCCESSFUL.
40. Turn OFF the ignition.
41. Turn OFF the Tech 2®.
42. Disconnect the Tech 2® from the vehicle.
43. Verify the control module programming was successful. Turn OFF the ignition for 30 seconds.
44. Start the engine. Repeat the Service Programming System procedure if the vehicle does not start or starts but runs rough.

Off-Board Remote Programming

Note. The Off-Board Programming Adapter Kit (J 41207-C) is required when a module must be programmed without having the vehicle present. The adapter allows the module to be turned ON and communicate with the scan tool.

1. Obtain the Vehicle Identification Number (VIN) of the vehicle for which the module is being programmed.
2. Launch the TIS application at the terminal.
3. Select the SERVICE PROGRAMMING SYSTEM.
4. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select Tech 2®. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select OFF-BOARD PROGRAMMING ADAPTER.
5. Select NEXT.
6. Follow the directions on the Preparing for Communication screen for connecting the following components: The control module. The Off-Board Programming Adapter (OBPA). Refer to the TIS users guide for a listing of the OBPA. The Tech 2®.
7. Select the SERVICE PROGRAMMING REQUEST INFORMATION function on the Tech 2®.
8. Follow the Tech 2® instructions to obtain the module data and security information.
9. After the Tech 2® has received the data from the module, exit the Request Info mode.
10. Disconnect the Tech 2® from the OBPA.
11. Turn OFF the Tech 2®.
12. Connect the Tech 2® to the terminal.
13. Turn ON the Tech 2®.
14. Select NEXT at the terminal after the Tech 2® start-up screen appears.
15. Enter the VIN of the vehicle that will be receiving the control module.
16. Select NEXT.
17. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
18. Select NEXT.
19. Select a calibration on the Calibration Selection screen, if necessary.
20. Ensure all the desired folder tabs have a green check mark.
21. Select NEXT.
22. Verify the current and the selected calibration of the control module on the Summary screen.
23. Select NEXT.
24. Select OK.
25. On model year 1996 and newer controllers, a Crankshaft Position (CKP) relearn procedure box may appear. Select OK.
26. Follow the on-screen instructions, if any, when the Program Controller/Programming Complete screen appears.
27. Select CLOSE.
28. Turn OFF the Tech 2®.
29. Disconnect the Tech 2® from the terminal.
30. Connect the Tech 2® to the OBPA.
31. Turn ON the Tech 2®.
32. Select Enter at the title screen.
33. Select the SERVICE PROGRAMMING SYSTEM at the Main Menu.
34. Select the PROGRAM ECU function.
35. Select CONTINUE.
36. Follow the on-screen instructions.
37. Select Continue.
38. Select EXIT when the programming is complete.
39. Turn OFF the OBPA.
40. Turn OFF the Tech 2®.
41. Disconnect the OBPA from the Tech 2® and the control module.

Off-Board Pass-Thru Programming

Note. The Off-Board Programming Adapter Kit (J 41207-C) is required when a module must be programmed without having the vehicle present. The adapter allows the module to be turned ON and communicate with the scan tool.

1. Launch the TIS application at the terminal.
2. Select the SERVICE PROGRAMMING SYSTEM.
3. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select PASS-THRU. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select OFF-BOARD PROGRAMMING ADAPTER.
4. Select NEXT.
5. Complete all terminal-directed data at the Preparing for Communication/Determine Vehicle screen until NEXT is highlighted.
6. Select NEXT.
7. Follow the on-screen instructions for connecting the following components: The control module. The Off-Board Programming Adapter (OBPA). Refer to the TIS users guide for a listing of the OBPA. The Tech 2®.
8. Select NEXT.
9. Pass-Thru displays the VIN stored in the control module. If a new control module is being programmed, enter the correct VIN of the vehicle.
10. Select NEXT.
11. Select the appropriate options if the Options screen appears.
12. Select NEXT.
13. Select the type of programming to be performed from the following categories: NORMAL - Used for updating an existing calibration or programming a new controller. VEHICLE CONFIGURATION INDEX (VCI) - Used for updating an existing controller or programming a new controller for newer vehicles whose VINs are not yet in the database. RECONFIGURE - Used to reconfigure a vehicle for changes in tire size and/or axle ratios.
14. Select NEXT.
15. Select a calibration on the Calibration Selection screen, if necessary.
16. Ensure all the desired folder tabs have a green check mark.
17. Select NEXT.
18. Verify the current and the selected calibration of the control module on the Summary screen.
19. Select NEXT.
20. Select OK.
21. On model year 1996 and newer controllers, a Crankshaft Position (CKP) relearn procedure box may appear. Select OK.
22. Follow the on-screen instructions, if any, when the Program Controller/Programming Complete screen appears.
23. Select CLOSE.
24. Turn OFF the OBPA.
25. Turn OFF the Tech 2®.
26. Disconnect the OBPA from the Tech 2® and the control module.

Pass-Thru Programming

Note. Pass-Thru programming allows the scan tool to remain connected to the terminal and to the vehicle throughout the programming process. The vehicle must be in close proximity to the terminal while using Pass-Thru.

1. Launch the TIS application at the terminal.
2. Select the SERVICE PROGRAMMING SYSTEM.
3. Highlight the following information on the Select Diagnostic Tool and Programming Process Screen: Select DIAGNOSTIC TOOL, then select PASS-THRU. Select PROGRAMMING PROCESS. Identify whether an existing module is being reprogrammed or a module is being replaced with a new one. Select ECU LOCATION. Select VEHICLE.
4. Select NEXT.
5. Complete all terminal-directed data on the Preparing for Communication/Determine Vehicle screen until NEXT is highlighted.
6. Select NEXT.
7. Follow the instructions on the Preparing for Communication screen.
8. Select NEXT.
9. Verify the VIN on the VALIDATE VEHICLE IDENTIFICATION NUMBER screen.
10. Select NEXT.
11. If an option screen appears, verify the vehicle configuration and/or RPO information.
12. Select NEXT.
13. Highlight the appropriate control module and programming type on the SUPPORTED CONTROLLERS screen.
14. Select NEXT.
15. Select the proper calibrations on the CALIBRATION SELECTION screen.
16. Ensure all the folder tabs have a green check mark.
17. Select NEXT.
18. Verify the current calibrations with the selected calibrations.
19. Select NEXT.
20. The TRANSFER DATA screen will appear until the progress bar reaches 100 percent. This may take up to 30 minutes.
21. Complete all of the terminal-directed data on the PROGRAMMING COMPLETE screen.
22. Turn OFF the Tech 2®.
23. Disconnect the Tech 2® from the vehicle.

Note. DO NOT use the old cap, CMP sensor, and rotor screws. Use the replacement screws that have been coated with a thread locking compound.

1. Remove the engine cover. Disconnect the spark plug wires and ignition coil wire from the distributor. (Scheme 37) Disconnect the camshaft position (CMP) sensor harness connector from the distributor. (Scheme 38)
2. Remove the distributor cap. (Scheme 39) Remove rotor screws and the rotor. (Scheme 40)
3. Align the square slot in the reluctor wheel with the CMP sensor. (Scheme 41) Remove the CMP screws. Remove the CMP sensor. (Scheme 42)
4. To install, insert the CMP sensor through the reluctor wheel slot. Install NEW cap, CMP sensor, and rotor screws. Install the rotor onto the reluctor wheel. Install the distributor cap. Connect the CMP sensor harness connector. Connect the spark plug wires and ignition coil wire. Install the engine cover.

Scheme 37

Scheme 38

Scheme 39

Scheme 40

Scheme 41

Scheme 42

Remove the engine cover. Disconnect the CMP sensor electrical connector. Remove the CMP sensor bolt. (Scheme 43) Remove the CMP sensor. To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 43

CRANKSHAFT POSITION SENSOR

Note. Vehicle requires CRANKSHAFT POSITION (CKP) SENSOR VARIATION LEARN PROCEDURE to be performed when CKP sensor is removed or replaced. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. When installing the CKP sensor, make sure the sensor is fully seated before tightening the mounting bolt. A poorly seated CKP sensor may perform erratically and may set false DTCs.

Raise the vehicle. Disconnect the CKP sensor harness connector. (Scheme 44) Remove the CKP sensor mounting bolt. Remove the CKP sensor. (Scheme 45) DO NOT use the original "O" ring. Lubricate the NEW "O" ring with clean engine oil before installing the CKP sensor. Ensure the CKP sensor mounting surface is clean and free of burrs. To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 44

Scheme 45

Note. Vehicle requires CRANKSHAFT POSITION (CKP) SENSOR VARIATION LEARN PROCEDURE to be performed when CKP sensor is removed or replaced. See COMPUTER RELEARN PROCEDURES article in GENERAL INFORMATION. When installing the CKP sensor, make sure the sensor is fully seated before tightening the mounting bolt. A poorly seated CKP sensor may perform erratically and may set false DTCs.

Disconnect the negative battery cable. Raise and support vehicle. Remove the starter. (Scheme 46) Disconnect the Crankshaft Position (CKP) sensor electrical connector. (Scheme 47) Clean the area around the CKP sensor before removal in order to avoid debris from entering the engine. Remove the CKP sensor retaining fastener. (Scheme 48) Remove the CKP sensor. To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 46

Scheme 47

Scheme 48

Note. Use care when handling the coolant sensor. Damage to the coolant sensor will affect the operation of the fuel control system. Replacement components must be the correct part number for the application.

1. Turn ignition off. Remove the engine cover. Drain the coolant below the level of the ECT sensor. Disconnect the electrical connector. Carefully remove the ECT sensor. (Scheme 49)or (Scheme 50)
2. Coat the threads with Sealer (GM 9985253). Install the ECT sensor. Tighten ECT sensor to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Connect the ECT sensor harness connector to the ECT sensor. Refill the cooling system. Install the engine cover.

Scheme 49

Scheme 50

Note. Numbers in parenthesis refer to numbers in illustration

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Drain the fuel tank. Remove the fuel tank. See «FUEL TANK»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).
2. Remove the fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Disconnect the fuel pump electrical connector (1). (Scheme 51) Remove the electrical connector retaining clip (2) from the fuel level sensor. Disconnect the electrical connector (3) from the fuel level sensor under the fuel sender cover. Remove the retaining clip (4) from the fuel level sensor. Squeeze the locking tangs and remove the fuel level sensor (5).
3. To install, reverse removal procedure. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 51

Remove the fuel sender assembly. See FUEL SENDER ASSEMBLY. Disconnect the fuel pump electrical connector (1). (Scheme 51) Remove the retaining clip (2) from the fuel level sensor connector. Disconnect the electrical connector (3) from under the fuel sender cover. Remove the sensor retaining clip (4). Squeeze the locking tangs and remove the fuel level sensor (5). To install, reverse removal procedure.

Disconnect the negative battery cable. Relieve the fuel pressure. See FUEL SYSTEM PRESSURE RELEASE. Raise and support vehicle. Remove the fuel tank. See FUEL TANK. Remove the fuel pressure sensor. (Scheme 52)or (Scheme 53). To install, reverse removal procedure. For vehicles equipped with 4.3L, turn the ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 52

Scheme 53

The Intake Air Temperature (IAT) sensor is combined with the Mass Air Flow (MAF) sensor. See MASS AIR FLOW SENSOR .

Note. The Knock Sensor (KS) is located at the top rear of the engine.

Disconnect the negative battery cable. Remove the engine cover. Disconnect the KS harness connector (1). (Scheme 54) Remove the KS bolt (2). Remove the KS (3). To install, reverse removal procedure. See TORQUE SPECIFICATIONS.

Scheme 54

Remove the intake manifold. See INTAKE MANIFOLD under AIR INDUCTION SYSTEMS. Remove the knock sensor wiring harness assembly. (Scheme 55) Remove the knock sensors. (Scheme 56) To install, reverse removal procedure. Tighten the sensors to specification. See TORQUE SPECIFICATIONS.

Scheme 55

Scheme 56

Note. Numbers in parenthesis refer to numbers in illustrations.

Turn ignition off. Disconnect the Mass Air Flow (MAF) sensor harness connector (1). (Scheme 57) Loosen the clamps (2) on the MAF sensor. Carefully remove the MAF (3) and IAT (4) sensor from the air intake duct. Ensure that the MAF sensor flow arrows point away from the air cleaner assembly. Install the MAF sensor into the air intake ducts. Tighten the clamps on the MAF sensor. Connect the MAF sensor harness connector.

Scheme 57

Disconnect the MAF/IAT sensor electrical connector. Remove the air cleaner assembly. Loosen the clamp securing the MAF/IAT sensor to the air cleaner duct. Remove the MAF/IAT sensor bolts from the air cleaner assembly. Remove the MAF/IAT from the air cleaner. To install, reverse removal procedure. The embossed arrow on the MAF/IAT sensor indicates the proper air flow direction. The arrow must point toward the engine. Tighten fasteners to specification. See TORQUE SPECIFICATIONS .

Note. Other than checking for a worn grommet and loose electrical connectors, the only service possible is a unit replacement if the diagnosis shows a malfunctioning Manifold Absolute Pressure (MAP) sensor. DO NOT rotate or pry on the MAP sensor when removing. Damage to the MAP sensor or the intake manifold may result.

Note. To locate MAP sensor (Scheme 58) DO NOT rotate or pry on the MAP sensor when removing. Damage to the MAP sensor or the intake manifold may result.

Turn ignition off. Remove the engine cover. Disconnect the MAP sensor harness connector. (Scheme 59) Remove the MAP sensor by pulling straight up with a slight rocking motion. (Scheme 60) Remove and discard the MAP sensor grommet. Install the NEW MAP sensor grommet on the MAP sensor. Install the MAP sensor. Connect the MAP sensor harness connector. Install the engine cover.

Scheme 58

Scheme 59

Scheme 60

Note. Numbers in parenthesis refer to number in illustrations

Remove the engine cover. Disconnect the MAP sensor electrical connector. Remove the MAP sensor (1) from the intake manifold. (Scheme 61) Lightly coat the MAP sensor with clean engine oil before installing the sensor. To install, reverse removal procedure.

Scheme 61

Note. Oxygen sensor is mounted in exhaust pipe, below exhaust manifold and is equipped with a permanent pigtail which must remain intact when removing sensor. (Scheme 62)

1. Ensure oxygen sensor is free of contaminants. DO NOT use cleaning solvents of any type. Oxygen sensor may be difficult to remove when engine temperature is above 120°F (48°C). Excessive removal force may damage threads in exhaust manifold or pipe.
2. Raise and support vehicle. Disconnect harness connector from oxygen sensor. Carefully remove oxygen sensor from exhaust pipe using Oxygen Sensor Socket (J 39194-B).

1. Whenever oxygen sensor is removed, coat threads with anti-seize compound before reinstallation. New oxygen sensors already have this compound applied to threads.
2. Install oxygen sensor in exhaust pipe. Tighten oxygen sensor to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) . Reconnect harness connector to oxygen sensor. Lower vehicle and test system.

Scheme 62

Note. The TP sensor is an electrical component. DO NOT soak the TP sensor in any liquid cleaner or solvent as damage may result.

Remove the engine cover. Remove the Throttle Position (TP) sensor harness connector. (Scheme 63) Remove the TP sensor attaching fasteners. (Scheme 64) Remove the TP sensor from the throttle body assembly. (Scheme 65) With the throttle valve closed, install the TP sensor on the throttle shaft. Rotate the TP sensor counterclockwise in order to align the mounting holes. Install the TP sensor attaching fasteners. Install the TP sensor harness connector. Install the engine cover.

Scheme 63

Scheme 64

Scheme 65

Note. The TP sensor is an electrical component. DO NOT soak the TP sensor in any liquid cleaner or solvent as damage may result.

Disconnect the negative battery cable. Remove the generator. (Scheme 66) Disconnect the throttle position (TP) sensor electrical connector. (Scheme 67) Remove the TP sensor attaching screws (1). (Scheme 68) Remove the TP sensor (2). Remove the TP sensor "O" ring seal (3). Install the TP sensor on the throttle body with the throttle valve in the closed position. Make sure the TP sensor lever lines up with the TP sensor drive lever on the throttle shaft. To complete installation, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 66

Scheme 67

Scheme 68

1. Remove the engine cover. Disconnect the Evaporative (EVAP) emission purge pipe.
2. Disconnect the purge valve electrical connector. (Scheme 69) Remove the two purge valve mounting nuts. Remove the engine wiring harness bracket from the mounting stud. Remove the purge valve from the intake manifold. (Scheme 70) To install, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 69

Scheme 70

Remove the air cleaner assembly. Push the Evaporative (EVAP) emission pipe quick connect fitting retainer inward. (Scheme 71) Disconnect the EVAP pipe (1) from the EVAP purge solenoid (2). (Scheme 72) Disconnect the EVAP purge solenoid electrical connector. Remove the EVAP purge solenoid mount bolt (1). (Scheme 73) Remove the EVAP purge solenoid (2) and the insulator (3) from the engine. To install, reverse removal procedure. Tighten fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 71

Scheme 72

Scheme 73

Raise the vehicle. Disconnect the electrical connector from the EVAP vent valve. (Scheme 74) Disconnect the canister vent hose. Bend back the tang on the bracket. Slide the EVAP vent valve off the bracket. (Scheme 75) To install, reverse removal procedure.

Scheme 74

Scheme 75

Removal (4.3L)

Note. If the Idle Air Control (IAC) valve has been in service, DO NOT push or pull on the IAC valve pintle. The force required to move the pintle may damage the threads on the worm drive. Also, DO NOT soak the IAC valve in any liquid cleaner or solvent, as damage may result.

Turn ignition off. Remove the engine cover. Disconnect the harness connector from the Idle Air Control (IAC) valve. Remove the IAC valve attaching fasteners. (Scheme 76) Remove the IAC valve assembly. Remove the "O" ring. (Scheme 77)

Scheme 76

Scheme 77

Cleaning and Inspection Procedure

Clean the IAC valve "O" ring sealing surface, the pintle valve seat, and the air passage. Use a carburetor cleaner and a parts cleaning brush in order to remove any carbon deposits. Follow the instructions on the container. DO NOT use a cleaner that contains Methyl Ethyl Ketone (MEK). MEK is an extremely strong solvent and not necessary for this type of deposit. Shiny spots on the pintle or seat are normal and DO NOT indicate misalignment or a bent pintle shaft. If the air passage has heavy deposits, remove the throttle body for a complete cleaning. See THROTTLE BODY . Inspect the IAC valve "O" ring for cuts, cracks, or distortion. Replace the "O" ring if damaged.

Note. If you are installing a new IAC valve, replace the valve with an identical part. The IAC valve pintle shape and diameter are designed for the specific application.

Measure the distance A between tip of the IAC valve pintle and the mounting flange. 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. Lubricate the IAC valve "O" ring with clean engine oil. Install the IAC valve assembly. Install the engine cover. Reset the IAC valve pintle position. See IAC VALVE RESET PROCEDURE .

IAC Valve Reset Procedure (4.3L)

Turn ignition on for 20 seconds. Turn ignition off for 10 seconds. Start the engine. Check for the proper idle speed.

Note. Numbers in parenthesis refer to numbers in illustrations.

Remove the generator. Disconnect IAC valve harness connector. Remove IAC valve retaining screws (1). (Scheme 78) Remove IAC valve (2) and "O" ring (3) from throttle body.

Scheme 78

Note. Before installation, clean "O" ring sealing surface, pintle seat and air passage. If air passage has heavy deposits, remove throttle body for complete cleaning.

1. Inspect "O" ring for damage. Replace as necessary. If reusing IAC valve, DO NOT push or pull on pintle. Threads on worm gear will be damaged.
2. If replacing IAC valve, measure distance between tip of new IAC valve pintle and mounting flange. Distance should not exceed 1 1/8" (28 mm). (Scheme 79) If distance is more than specified, use finger pressure to slowly retract pintle. Lubricate "O" ring with clean engine oil.
3. Apply Thread Locking Compound (Loctite 262) to IAC valve retaining screw threads. Install IAC valve to throttle body. Tighten IAC valve retaining screws to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Reconnect IAC valve harness connector.
4. To reset IAC valve pintle position, turn ignition on for 20 seconds. Turn ignition off for 10 seconds. Start engine and check for proper idle operation. Repeat procedure if proper idle operation is not obtained.

Scheme 79

4.3L

Place a large funnel in radiator filler neck. Pour one-half of cooling system capacity of DEX-COOL® coolant into radiator. Fill remaining capacity with clean, drinkable water to 0.5" below radiator filler neck. Start engine and let cooling system warm up. If coolant level drops when thermostat opens, add clean drinkable water to just below filler neck. Install radiator cap and top off reservoir. Check for leaks.

4.8L, 5.3L & 6.0L

Place a funnel into the upper radiator hose. Use a 50/50 mixture of DEX-COOL® antifreeze and clean, drinkable water. Slowly fill the cooling system through the upper hose with a 50/50 coolant mixture until the coolant comes out of the coolant air bleed hose. Connect the upper radiator hose to the radiator. Using the Hose Connector (J38185), position the hose clamp into the original position on the hose. Connect the coolant air bleed hose at the radiator. Fill the radiator with coolant through the filler neck. Rinse away any excess coolant from the engine and the engine compartment.

FUEL SYSTEMS

FUEL SYSTEM PRESSURE RELEASE

Fuel system is under pressure. Pressure must be released prior to servicing fuel system. Disconnect negative battery cable. Loosen fuel filler cap. Install Fuel Pressure Gauge (J-34730-1A) on fuel pressure connector of fuel rail. Wrap a shop towel around pressure connection when installing fuel pressure gauge to absorb fuel leakage. Place gauge bleed hose in container. Open bleed valve to release fuel pressure.

Removal & Installation (Metal Collar)

1. Disconnect negative battery cables. Remove the fuel filler cap. Remove the retainer from the quick-connect fitting. Blow dirt out of the fitting using compressed air. Choose the correct end from Fuel Line Disconnect Tool (J 44581) the for the size of the fitting. Insert the tool into the female connector, then push inward in order to release the locking tabs. Pull the connection apart.
2. 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. Use a clean shop towel in order to wipe off the male tube ends. Inspect all the connections for dirt and burrs. Clean or replace the components and assemblies as required.
3. Apply a few drops of clean engine oil to the male pipe end. Push both sides of the fitting together in order to snap the retaining tabs into place. Once installed, pull on both sides of the fitting to ensure the connection is secure.

Removal & Installation (Plastic Collar)

1. Grasp both sides of the quick-connect fitting. Twist the female connector 1/4 turn in each direction in order to loosen any dirt within the quick-connect fitting. Use compressed air in order to blow any dirt out of the quick-connect fitting. Release the locking tabs by squeezing the tabs with the thumb and index finger. Insert the tool into the female connector, then push inward to release the locking tabs. Pull the connection apart.
2. Use an emery cloth in order to remove rust or burrs from the fuel pipe. Use a radial motion with the fuel pipe end in order to prevent damage to the "O" ring sealing surface. Use a clean shop towel in order to wipe off the male fuel pipe end. Inspect both ends of the quick-connect fitting for dirt and burrs. Clean or replace the components/assemblies as required.
3. Apply a few drops of clean engine oil to the male fuel pipe end. Push both sides of the quick-connect fitting together in order to cause the retaining tabs/fingers to snap into place. Once installed, pull on both sides of the quick-connect fitting in order ensure that the connection is secure.

FUEL SYSTEM CLEANING

1. Disconnect the negative battery cable. Relieve fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release) . Drain fuel tank. Remove the fuel tank. See «FUEL TANK»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) . Remove fuel pump module. See «FUEL TANK PUMP MODULE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) . Inspect the fuel 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.
2. Flush the fuel tank with hot water. Pour the water out of the fuel sender assembly opening. Rock the tank to ensure that removal of the water from the tank is complete. Inspect the fuel filter for contamination. Replace the fuel filter if the filter is plugged. See «FUEL FILTER»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) .
3. Clean the fuel lines by applying air pressure in the opposite direction of the fuel flow. Install the fuel pump module with NEW seal into the fuel tank. Install the fuel tank. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Note. Inspect the fuel tank internally and clean the fuel tank if you find a restricted fuel filter. See FUEL SYSTEM CLEANING .

1. Disconnect the negative battery cable. On Cutaway Van, remove the mounting bolts from the EVAP canister bracket. On all models, relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Raise and support the vehicle.
2. Disconnect the fuel feed pipe from the fuel filter outlet. Disconnect the fuel feed pipe from the fuel filter inlet. (Scheme 80)or (Scheme 81). Clean all the fuel filter connections and the surrounding areas before disconnecting the fuel pipes in order to avoid possible contamination of the fuel system.
3. Cap the fuel pipes in order to prevent fuel system contamination. Remove the fuel filter from the bracket. Inspect the fuel pipe "O" rings for cuts, nicks, swelling or distortion. Replace the "O" rings if necessary.
4. Install the fuel filter into the bracket. Remove the caps from the fuel pipes. Connect the fuel feed pipe to the fuel filter inlet. To complete installation, reverse removal procedure. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 80

Scheme 81

Note. An 8-digit part identification number is on a mylar label affixed to the fuel meter body assembly. Refer to this number if servicing or part replacement is required. DO NOT use any solvent that contains Methyl Ethyl Ketone (MEK). This solvent may damage fuel system components. Before removal, clean the fuel meter body assembly with a spray type engine cleaner (GM X-30A or equivalent), if necessary. Follow the package instructions. DO NOT soak the fuel meter body assembly in liquid cleaning solvent.

Note. The number 3 fuel tube must be positioned behind the number 1 fuel tube to eliminate interference with the upper intake manifold when installed.

1. Disconnect negative battery cable. Release fuel pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release) . Disconnect harness connectors from fuel meter body. Disconnect fuel feed and return lines. Remove upper intake manifold assembly. See «INTAKE MANIFOLD»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) under AIR INDUCTION SYSTEMS.
2. Label injector lines for installation reference. Squeeze injector lock tabs and lift injectors from lower intake manifold. Remove fuel meter body from bracket with injector lines and injectors attached by releasing lock tabs on bracket. Disassemble as necessary.
3. To install, reverse removal procedure. Verify that the poppet nozzles are firmly seated and locked in their casting sockets in order to reduce the risk of fire and personal injury. An unlocked poppet nozzle could work loose from its socket and produce a fuel leak.
4. Bleed cooling system. See «COOLING SYSTEM BLEEDING»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) under COOLING SYSTEM. Ensure all injectors are properly locked into place.
5. Install NEW "O" ring onto fuel feed and return lines. Tighten all nuts and bolts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) .

See FUEL LEVEL SENSOR under SENSORS & SWITCHES.

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Remove the engine cover. Remove the upper intake manifold assembly. See «REMOVAL & INSTALLATION (4.3L - UPPER)»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__removal-43l-upper-intake-manifold) in INTAKE MANIFOLD under AIR INDUCTION SYSTEMS.
2. Remove the fuel pressure regulator retainer clip (1). (Scheme 82) Pull and twist the fuel pressure regulator (2) in order to remove the fuel pressure regulator from the fuel pressure regulator housing using a shop towel to catch any spilled fuel. Remove the regulator seal lower "O" ring (3). Remove the regulator assembly filter (4).
3. Remove the regulator seal upper "O" ring (5). Remove the regulator seal backup ring (6). Cover the fuel pressure regulator housing to prevent contamination from entering the fuel system. Discard the "O" rings.
4. Lubricate the NEW "O" rings with clean engine oil. Install the regulator seal backup ring. Install the regulator seal upper "O" ring. Install the regulator assembly filter. Install the regulator seal lower "O" ring. Assemble the regulator with the vacuum tube pointing down into the regulator retainer clip. Install the fuel pressure regulator retainer clip. To complete installation, reverse removal procedure.

Scheme 82

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Remove the engine cover. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Disconnect the fuel pressure regulator vacuum line. Clean any dirt from the fuel pressure regulator retainer and the surrounding area.
2. Remove the fuel pressure regulator retainer (1). (Scheme 83) Remove the fuel pressure regulator (2).
3. Ensure that the backup ring (3), regulator seal "O" ring (4 and 6) and regulator filter (5) are not still in the fuel rail.
4. Ensure that the NEW fuel pressure regulator retainer is the correct one. (Scheme 84) The tabs (1) are used on the straight vacuum port retainer (2), and the E85 straight vacuum port retainer (3). The angle vacuum port retainer (4) has no tabs.
5. Install the following parts onto the fuel pressure regulator (9), if necessary: Backup ring (10) Regulator seal "O" ring (11) Regulator filter (12) Regulator seal "O" ring (13) Lubricate the fuel pressure regulator "O" rings (11, 13) with clean engine oil. Install the fuel pressure regulator (9).
6. Install the NEW fuel pressure regulator retainer (8). Connect the fuel pressure regulator vacuum line. Tighten the fuel fill cap.
7. Connect the negative battery cable. Tighten the fuel filler cap. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks. Install the engine cover.

Scheme 83

Scheme 84

Fuel pump is located in fuel tank and is integral with fuel sender assembly. Fuel pump must be replaced with fuel sender as an assembly. See FUEL SENDER ASSEMBLY .

FUEL RAIL & INJECTORS

Note. Use care in removing the fuel injectors to prevent damage to the electrical connector terminals. The fuel injector is serviced as a complete assembly only. Since the injectors are electrical components, these injectors should not be immersed in any type of liquid solvent or cleaner as damage may occur. Fuel injector cleaning is not recommended.

1. Remove the fuel meter body assembly. See «FUEL METER BODY ASSEMBLY & INJECTORS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Remove the injector assembly retainer (1) and the injector retainer lock nuts (2). (Scheme 85)
2. While pulling the poppet nozzle tube downward, push with a small tip punch down between the injector terminals until the injector is removed.
3. Lubricate the new injector "O" ring seals with clean engine oil. (Scheme 86) Install the "O" rings on the injector assembly.
4. Install the fuel injector assembly (3) into the injector socket. Install the injector assembly retainer (1) and the injector retainer lock nuts (2). Tighten the lock nuts to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Install the fuel meter body assembly. See «FUEL METER BODY ASSEMBLY & INJECTORS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 85

Scheme 86

Note. Before removal, if necessary, clean the fuel rail assembly with a spray type engine cleaner, use GM X-30A or equivalent. Follow the package instructions. DO NOT soak fuel rail assembly in any liquid cleaning solvent.

Note. Use care in removing the fuel injectors in order to prevent damage to the fuel injector electrical connector pins or the fuel injector nozzles. DO NOT immerse the fuel injector in any type of cleaner. The fuel injector is an electrical component and may be damaged by this cleaning method.

1. Remove the engine cover. Remove the air cleaner resonator outlet duct.
2. Disconnect the accelerator control cable and the cruise control cable from the cable bracket, if equipped. Disconnect the cruise control cable engine-end fitting from the stud on the throttle lever, if equipped. (Scheme 88)
3. Disconnect the accelerator control cable and the cruise control cable from the throttle body, if equipped. Remove the upper engine wire harness retainer nut. (Scheme 89)
4. Disconnect the Evaporative (EVAP) Emission purge valve harness connector. Reposition the upper engine wire harness aside. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release).
5. Mark the electrical connectors to their corresponding injectors to ensure correct sequential injector firing order after reassembly.
6. Pull the Connector Position Assurance (CPA) (2) on the injector connector up. Push the tab (1) on the injector connector in. While pushing the tab (1) on the injector connector in, release the CPA (2). (Scheme 90)
7. Repeat step 6 for the remaining fuel injector connector electrical connectors. (Scheme 91)
8. Disconnect the fuel feed and return pipes from the fuel rail. Disconnect the fuel pressure regulator vacuum line. Loosen the crossover tube to right fuel rail retainer screw. (Scheme 92) Remove the fuel rail bolts. Remove the fuel rail. Remove and discard the fuel injector lower "O" ring seals from the injectors. (Scheme 93)

Scheme 87

Scheme 88

Scheme 89

Scheme 90

Scheme 91

Scheme 92

Scheme 93

1. The fuel injector (1) is stamped with a part number identification (2). A four-digit build date code (3), which indicates the month (4), day (5), year (6), and the shift (7) that built the fuel injector. (Scheme 94)
2. Lubricate the NEW fuel injector lower "O" ring seals with clean engine oil. Install the NEW "O" ring seals to the end of each injector. (Scheme 93)
3. Install a NEW crossover pipe "O"ring on the crossover pipe. Install the crossover pipe into the right fuel rail. Loosely install the crossover pipe retainer and retaining clip attaching screw to the right fuel rail. Install the fuel rail. Install the fuel rail bolts.
4. To complete installation procedure, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).
5. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks. Install the engine cover.

Scheme 94

Note. 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.

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Drain the fuel tank. Remove the fuel tank. See «FUEL TANK»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).
2. Remove the retaining ring from the fuel sender assembly using Fuel Sender Lock Nut Wrench (J 39765). Remove the fuel sender assembly and the seal. (Scheme 95) Discard the seal. Clean the fuel sender sealing surfaces.
3. Install the NEW seal on the fuel tank. Install the fuel sender assembly into the fuel tank. To complete installation, reverse removal procedure.
4. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks. Install the engine cover.

Scheme 95

Removal & Installation (Passenger/Cargo Van)

Note. Numbers in parenthesis refer to numbers in illustrations.

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Drain the fuel tank. Raise the vehicle.
2. Disconnect the fuel fill hose from the fuel fill pipe. (Scheme 96) Clean all the fuel pipe connections and the surrounding areas before disconnecting the fuel pipes in order to avoid possible contamination of the fuel system. Disconnect the rear fuel return pipe at the chassis fuel return pipe. Disconnect the chassis fuel feed pipe at the fuel filter. Disconnect the chassis Evaporative (EVAP) emission purge pipe at the EVAP canister. Cap the fuel and EVAP pipes in order to prevent fuel system contamination.
3. With the aid of an assistant, support the fuel tank. Remove the attaching bolts (1) from the fuel tank strap. (Scheme 97) Remove the fuel tank straps (2). Carefully lower the fuel tank. Disconnect the fuel sender and the fuel pressure sensor electrical connectors. Remove the fuel tank. Place the fuel tank in a suitable work area.
4. Disconnect the EVAP pipe at the front roll-over valve (1), the rear roll-over valve (2), the EVAP canister (3), and the retainer clips. (Scheme 98) Remove the fuel sender assembly and the fuel pipes (4) from the fuel tank and the fuel filter. Remove the fuel fill hose from the fuel tank. Remove the fuel tank from the fuel tank shield.
5. To install, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Inspect for leaks. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 96

Scheme 97

Scheme 98

Removal & Installation (Cutaway Van Rear Tank)

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Drain the fuel tank. Raise the vehicle. This must be done with a frame hoist in order to allow the rear suspension to hang.
2. Loosen the fuel fill hose clamp (1). (Scheme 99) Disconnect the fuel fill hose (2) from the fuel tank (3).
3. Clean all the fuel pipe connections and the surrounding areas before disconnecting the fuel pipes in order to avoid contamination of the fuel system. Disconnect the rear fuel and Evaporative (EVAP) emissions pipes (1) at the chassis fuel and EVAP pipes. (Scheme 100)
4. Cap the fuel and EVAP pipes in order to prevent fuel system contamination. With the aid of an assistant, support the fuel tank. Remove the attaching bolts (1) from the fuel tank strap. (Scheme 101) Remove the fuel tank straps (2). Carefully lower the fuel tank (3). Disconnect the electrical connectors from the fuel sender and the fuel pressure sensor. Remove the fuel tank. Place the fuel tank in a suitable work area.
5. Remove the fuel sender assembly and the rear fuel and EVAP pipes from the fuel tank. See «FUEL SENDER ASSEMBLY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).
6. To install, reverse removal procedure. Inspect for leaks. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 99

Scheme 100

Scheme 101

Removal & Installation (Cutaway Van Side Tank)

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release). Drain the fuel tank. Raise and support the vehicle.
2. Clean all fuel pipe and hose connections and surrounding areas before disconnecting the fuel pipes in order to avoid contamination of the fuel system. Loosen the fuel fill hose clamp. Disconnect the fuel fill hose from the fuel fill pipe. (Scheme 102) Disconnect the rear Evaporative (EVAP) emission pipe at the EVAP canister.
3. With the aid of an assistant, support the fuel tank. Remove the attaching bolts (1) from the fuel tank strap. Remove the fuel tank straps (2). Carefully lower the fuel tank. Disconnect the fuel feed pipe and the fuel return pipe at the fuel sender. See «REMOVAL & INSTALLATION (PLASTIC COLLAR)»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__removal-installation-plastic-collar) in QUICK CONNECT FITTINGS. Disconnect the electrical connectors from the fuel sender and the fuel pressure sensor. Remove the fuel tank.
4. Place the fuel tank in a suitable work area. Cap the open fuel and EVAP pipes on the vehicle in order to prevent possible fuel system contamination. Remove the EVAP pipe from the roll over valves and the retainer clips. Remove the fuel sender assembly from the fuel tank. See «FUEL SENDER ASSEMBLY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Remove the fuel fill hose from the fuel tank.
5. To install, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline). Inspect for leaks. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

Scheme 102

Scheme 103

1. Disconnect the negative battery cable. Relieve the fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-pressure-release) . Drain the fuel tank. Remove the fuel tank. See «FUEL TANK»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) . Remove the fuel sender assembly. See «FUEL SENDER ASSEMBLY»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) .
2. Note the position of the fuel strainer on the fuel sender. Support the fuel sender assembly with one hand and grasp the strainer with the other hand. Pull the strainer off the fuel sender. Inspect the strainer. Discard the strainer after inspection. If strainer is contaminated, clean the fuel tank. See «FUEL SYSTEM CLEANING»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline__fuel-system-cleaning) . Disconnect the fuel pump electrical connector. Remove the electrical connector retaining clip from the fuel level sensor. Disconnect the electrical connector from the fuel level sensor under the fuel sender cover. Remove the retaining clip from the fuel level sensor. Squeeze the locking tangs and remove the fuel level sensor. Remove the fuel pressure sensor.
3. Install the fuel pressure sensor. Install the fuel level sensor. Install the retaining clip to the fuel level sensor. Connect the electrical connector to the fuel level sensor. Connect the electrical connector retaining clip. Connect the fuel pump electrical connector. Install a NEW fuel strainer in the same position as noted during disassembly. Push the strainer on the bottom of the fuel sender until the strainer is fully seated. To complete installation, reverse removal procedure. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) . Connect the negative battery cable. Inspect for leaks. Turn ignition on for 2 seconds. Turn ignition off for 10 seconds. Turn ignition on. Inspect for fuel leaks.

See FUEL TANK PRESSURE SENSOR under SENSORS & SWITCHES.

See OXYGEN SENSOR under SENSORS & SWITCHES.

See THROTTLE BODY under AIR INDUCTION SYSTEMS.

See CAMSHAFT POSITION SENSOR under SENSORS & SWITCHES.

See CRANKSHAFT POSITION SENSOR under SENSORS & SWITCHES.

DISTRIBUTOR

Note. The 4.8L, 5.3L & 6.0L are distributorless.

1. Turn ignition off. Disconnect negative battery cable. Loosen hose clamp on outlet side of Mass Airflow (MAF) sensor. Dislodge air cleaner outlet duct from outlet side of MAF sensor.
2. Remove air cleaner outlet duct wing nut at throttle body unit. Pivot air cleaner outlet duct/resonator upward at throttle body unit until hinge clip releases from lip on throttle body. (Scheme 104)
3. Reference mark spark plug wires at distributor cap for reassembly. Slightly twist all spark plug wires and ignition coil wire at distributor cap. Remove all spark plug wires and ignition coil wire at distributor cap by pulling on the wire boot.
4. Disconnect harness connector at base of distributor. Remove distributor cap retaining screws and distributor cap. Using a grease pencil, mark position of the distributor rotor in relation to the distributor housing. Make another mark on the intake manifold in relation to the mark made on the distributor housing.
5. Remove distributor hold-down bolt. Lift distributor upward while observing counterclockwise rotation of distributor rotor. Once distributor is fully removed, place a second reference mark on the distributor housing in relation to the distributor rotor position.

Installation (Engine Has Been Rotated With Distributor Removed)

1. If engine was rotated after distributor was removed, remove No. 1 spark plug. Place finger over cylinder No. 1 spark plug hole. Crank engine slowly until compression is felt. The 2 marks on the crankshaft pulley should align with the 2 engine front cover tabs. (Scheme 105) If necessary, rotate engine by hand until timing marks are fully aligned.
2. Align White paint mark on bottom stem of distributor and the pre-drilled indent hole in the bottom of the gear. (Scheme 106) Using a long screwdriver, align the oil pump driveshaft to the drive tab on the distributor.
3. Carefully lower distributor into engine with flat side of distributor housing facing toward front of vehicle. (Scheme 107) Once distributor is fully seated, distributor rotor should be aligned with pointer cast into distributor housing.
4. If distributor rotor is not properly aligned, remove distributor and repeat procedure until mark aligns properly. Install distributor hold-down bolt and tighten to specification. To complete installation, reverse removal procedure. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 104

Scheme 105

Scheme 106

Scheme 107

Installation (Engine Has Not Been Rotated With Distributor Removed)

1. To ensure correct timing of distributor, install with rotor positioned as it was when distributor was removed. Align distributor rotor with last mark made on distributor housing. Align bolt hole in distributor hold-down with threaded hole in intake manifold.
2. Carefully lower distributor into engine. Distributor rotor should turn clockwise and line up with first reference mark made on distributor housing once fully seated into engine. Bolt hole in distributor hold-down should still be aligned with threaded hole in intake manifold.
3. If distributor rotor is not properly aligned, remove distributor and repeat procedure until mark aligns properly. Install distributor hold-down bolt and tighten to specification. To complete installation, reverse removal procedure. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline) .

1. Remove the air cleaner assembly and nut. Disconnect the electrical connectors. Remove the ignition coil wire to the distributor. (Scheme 108) Remove the accelerator cable bracket. Remove the studs holding the bracket and the ignition coil to the intake manifold. Remove the bracket and the ignition coil. Drill and punch out the two rivets holding the ignition coil to the bracket. Remove the ignition coil from the bracket.
2. A replacement ignition coil kit comes with 2 screws in order to attach the ignition coil to the bracket. Install the ignition coil to the bracket with the 2 screws. (Scheme 109) Install the ignition coil and the bracket to the intake manifold with studs. Install the accelerator control bracket. Install the ignition coil wire. The wire must not touch anything like the dip stick. Rubbing will make a ground or short after time of use. Install the electrical connectors. Install the air cleaner assembly and nut.

Scheme 108

Scheme 109

Remove the engine cover. Disconnect the spark plug wires at the ignition coils. Disconnect the ignition coil harness connector. (Scheme 110) Remove the ignition coil mounting bolts. (Scheme 111) Remove the ignition coil. Install the ignition coil to the bracket. To install reverse removal procedure. Tighten ignition coil bolts to specification. See TORQUE SPECIFICATIONS.

Scheme 110

Scheme 111

Remove the engine cover. Disconnect the electrical connector. Remove the screws holding the ignition control module and the heat sink to the bracket. Remove the ignition control module and the heat sink. Install the ignition control module and the heat sink on the bracket with the screws. Reconnect the electrical connectors. Install the engine cover.

See KNOCK SENSOR under SENSORS & SWITCHES.

Remove the spark plug wires. Loosen each spark plug 1 or 2 turns. Brush or air blast away any dirt from around the spark plugs. Remove the spark plugs 1 at a time. Place each plug in a tray marked with the corresponding cylinder number. Inspect each spark plug gap. Adjust each plug as needed. Tighten to specification. See TORQUE SPECIFICATIONS .

Removal & Installation (Cutaway Van)

Raise the vehicle. Remove the EVAP canister bracket bolt. Disconnect the vent hose from the canister. Disconnect the chassis EVAP purge pipe from the EVAP canister. Disconnect the fuel tank EVAP pipe from the canister. Remove the EVAP canister from the bracket. To install, reverse removal procedure.

Raise the vehicle. Remove the EVAP canister retainer. Disconnect the vent hose from the canister. Disconnect the chassis EVAP purge pipe from the EVAP canister. Disconnect the fuel tank EVAP pipe from the canister. Remove the EVAP canister from the fuel tank shield. To install, reverse removal procedure.

See EVAP CANISTER PURGE VALVE under MOTORS, RELAYS & SOLENOIDS

See EVAP CANISTER VENT VALVE under MOTORS, RELAYS & SOLENOIDS.

1. Remove the engine cover. Remove the retaining fastener from the EGR pipe bracket. (Scheme 112) Loosen the pipe fittings at both ends of the EGR pipe. Remove the EGR pipe.
2. Install the EGR pipe in the proper location and start the pipe fittings by hand. Ensure that the EGR pipe fittings are correctly lined up on the adaptors to the exhaust and the intake manifolds. Tighten the EGR pipe fittings to the intake manifold and the exhaust manifold. To complete installation, reverse removal procedure. Tighten fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 112

Remove the exhaust gas recirculation (EGR) valve. See REMOVAL & INSTALLATION (EGR VALVE - 4.8L, 5.3L & 6.0L). Remove the EGR pipe to intake manifold fasteners (1) and discard "O" ring. (Scheme 113) Remove the EGR pipe to exhaust manifold fasteners (2) and discard gasket. Remove the EGR pipe mounting fasteners from the right cylinder head (3). Remove the EGR pipe (4). To install, reverse removal procedure. Use NEW "O" ring and gasket. Tighten all fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 113

Note. DO NOT try to disassemble the linear EGR valve. Service the EGR valve only as a complete assembly. DO NOT soak in any liquid cleaner or solvent because Linear EGR valve is an electrical component. Damage may result. Carefully note the position of the linear EGR valve before removal. DO NOT rotate the linear EGR valve 180 degrees.

1. Disconnect the negative battery cable. Remove the air cleaner assembly. Remove the linear EGR harness connector. (Scheme 58) Remove the bolts attaching the linear EGR valve to the flange. (Scheme 114) Remove the linear EGR valve. Remove and discard the flange gasket. (Scheme 115)
2. Clean the EGR valve gasket surface. Install NEW flange gasket. Install the linear EGR valve. To complete installation, reverse removal procedure. Tighten all fasteners to specification. See «TORQUE SPECIFICATIONS»(/chevrolet/chevy-express-h2500/2003-2003/remont/removal-installation/#engine-controls-removal-installation-gasoline).

Scheme 114

Scheme 115

Note. DO NOT try to disassemble the linear EGR valve. Service the EGR valve only as a complete assembly. DO NOT soak in any liquid cleaner or solvent because Linear EGR valve is an electrical component. Damage may result. Carefully note the position of the linear EGR valve before removal. DO NOT rotate the linear EGR valve 180 degrees.

Note. The EGR valve is an electrical component. Soaking the EGR valve in a liquid cleaner or a solvent causes damage to the valve.

Remove the air cleaner assembly. Disconnect the EGR electrical connector. Remove the valve to flange attaching fasteners. (Scheme 116) Remove the EGR valve. Remove the flange gasket. Clean the EGR valve gasket surface. Install NEW flange gasket. Install the linear EGR valve. To complete installation, reverse removal procedure. Tighten all fasteners to specification. See TORQUE SPECIFICATIONS.

Scheme 116

EGR System Cleaning (All Models)

Note. Damage to the powdered metal EGR valve base occurs if cleaned with a wire brush, a wire wheel, solvents, sharp tools, or sand blasting. Cleaning by these methods is not recommended.

Remove the EGR valve. See REMOVAL & INSTALLATION (EGR VALVE - 4.3L) or REMOVAL & INSTALLATION (EGR VALVE - 4.8L, 5.3L & 6.0L) . Depress the pintle several times using a pencil eraser or other suitable soft instrument. The pintle should move in and out smoothly. Replace the valve if the valve exhibits tendencies to stick. Try to rotate the EGR valve electrical connector housing. Repeat for the coil housing. Replace the valve if the valve exhibits any looseness. Inspect the EGR valve pintle and seat for deposits. Use a cloth or other suitable soft device to remove the deposits. Remove all loose particles. Replace the valve if the deposits are such that the pintle to base interface cannot be cleaned adequately to allow the pintle to seal against the seat. Remove the EGR pipe. See REMOVAL & INSTALLATION (EGR PIPE) . Clean the passages with a wire brush. Remove all loose particles. Install the EGR pipe. Install the EGR valve.

TORQUE SPECIFICATIONS (4.3L)

TORQUE SPECIFICATIONS (4.8L, 5.3L & 6.0L)

See also:
• FUEL INJECTION CONTROL MODULE
• EVAP CANISTER PURGE VALVE
• DISTRIBUTOR
• REMOVAL (4.3L - UPPER INTAKE MANIFOLD)
• FUEL RAIL & INJECTORS (SFI)
• FUEL SYSTEM PRESSURE RELEASE
• IAC VALVE RESET PROCEDURE
• FUEL SYSTEM CLEANING
• REMOVAL & INSTALLATION (PLASTIC COLLAR)
• CRANKSHAFT POSITION SENSOR