Engine Controls - Removal & Installation: Overhaul Pontiac Sunfire I

Disassembly Procedure

Note. Shipping regulations prohibit transporting a fuel tank containing CNG. Vent the fuel tank before shipping it.

Note. Numbers in text refer to numbered components in illustration. see scheme 66

If replacing the tank, remove the following components

1. Remove rubber isolators.
2. Remove Fuel Tank Pressure (FTP) sensor (2).
3. Remove fuel inlet fitting (3) from the tank valve.
4. Remove fuel outlet fitting (1) from the tank valve.
5. Remove HPL Pressure Relief Device (PRD) line fitting (4) from the tank valve.
6. Remove vent boot.
7. Remove and discard the CNG Fuel Only label from the fill door.
8. Remove and discard the Bi-fuel Information label from the underhood area.

Assembly Procedure

If replacing the tank, install the following components

1. Install the vent boot. Tighten the vent boot clamp to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000) .
2. Install the fuel outlet fitting (1) to the tank valve using a new "O" ring. Lubricate the new "O" ring face seal with petroleum jelly or the equivalent. Tighten the fitting to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000) .
3. Install the fuel inlet fitting (3) to the tank valve using a new "O" ring. Lubricate the new "O" ring face seal with petroleum jelly or the equivalent. Tighten the fitting to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000) .
4. Install the FTP sensor (2) using a new "O" ring face seal. Lubricate the new "O" ring with petroleum jelly or the equivalent. Tighten the FTP sensor to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000) .
5. Install the HPL Pressure Relief Device line fitting (4) in the tank valve. Tighten the fitting to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000) .
6. Install the new rubber isolators.
7. Obtain a new CNG Fuel Only label and a new Bi-fuel Information label.
8. Record the new tank service expiration date on each label.
9. Install the new labels.

1. Install the CNG Tank Remover into the tank strap bolt holes. see scheme 57 The straps are not required for installation.
2. Lower the tank onto the CNG Tank Remover using a lifting device and the CNG Tank Sling. see scheme 60
3. Roll the tank to the proper position using the orientation marks.
4. Raise the CNG Tank Remover and roll the tank into position in the tank cradle.
5. Verify the alignment of the HPL inlet fitting. The fitting should be at the 3 o'clock position.
6. The HPL should be 10.5" (26.7 cm) from the left edge of the left tank strap. (Scheme 20)
7. Remove the CNG Tank Remover from the bracket.
8. Install the tank straps.
9. Install the tank strap bridge pins and the clevis pins. see scheme 56
10. Install the NEW tank strap bolts and the NEW nuts. see scheme 55 Tighten the tank strap nuts to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
11. Install the Pressure Relief Device (PRD) line and the HPL to HPR lines and the vent hose as an assembly. (Scheme 21)
12. Connect the PRD and the HPL to HPR lines using new "O" ring face seals. Lubricate the "O" rings with petroleum jelly, or equivalent. Tighten the PRD line fitting to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
13. Install the fill valve to union fill line using new "O" ring face seals. Lubricate the "O" rings with petroleum jelly or the equivalent. Tighten the fill line fittings to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
14. Install the union to HPL fill line using new "O" ring face seals. Lubricate the "O" rings with petroleum jelly or the equivalent. Tighten the fill line fittings to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
15. Connect the harness connectors and the HPL power connector.
16. Connect the negative battery cable. Tighten to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
17. Fill the CNG fuel system.
18. Start the engine. Check for CNG fuel leaks at each serviced fitting using the Combustible Gas Detector (J 45878), or equivalent.
19. Position the 4 hose clamps at the vent boot, the vent hose and the fill valve boot. Tighten the four hose clamps to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
20. Install the vent boot cover and the cover nuts. Tighten the vent boot cover nuts to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
21. Install the left side trunk carpet.
22. Install the cargo net knobs and the cargo net.
23. Install the trunk trim.
24. Install the spare tire bracket and the spare tire bracket bolts. see scheme 54 Tighten the spare tire bracket bolts to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).
25. Install the fuel tank cover. Tighten the fuel tank cover nuts to specification. See «TORQUE SPECIFICATIONS»(ref-153402-S15109679952003040400000).

Scheme 20

Scheme 21

FUEL SENDER ASSEMBLY

Note. Fuel level sensor and fuel tank pressure sensor are removed as an assembly with the fuel sender assembly which also includes the fuel pump and fuel strainer. When installing fuel sender assembly, DO NOT fold or twist strainer. This will restrict fuel flow.

Note. Numbers in parenthesis correspond to numbered components in referenced illustration.

Fuel sender assembly is located in the fuel tank. (Scheme 22)

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE (GASOLINE)»(ref-153402-S34229557402003040400000) .
2. Remove fuel tank. See «FUEL TANK (GASOLINE)»(ref-153402-S19914623502003040400000) .
3. Use the Fuel Sender Lock Nut Wrench (J 39765) to press down and rotate the retaining ring (1).
4. Remove the fuel sender assembly.
5. Remove the fuel level sensor from the fuel sender assembly. See «FUEL LEVEL SENSOR»(ref-153402-S07791538982003090300000) .

Scheme 22

1. Install the fuel level sensor to the fuel sender assembly. See «FUEL LEVEL SENSOR»(ref-153402-S07791538982003090300000).
2. Install the new seal on the fuel tank (4). (Scheme 22)
3. Align the fuel pipes parallel with the mark on the fuel tank.
4. Slowly apply pressure to the top of the spring loaded sender until the sender aligns flush with the retainer on tank.
5. Install the retaining ring (1) using the fuel sender lock nut wrench.
6. Connect the wiring harness to the fuel sender and the FTP sensor.
7. Install the fuel tank. See «FUEL TANK (GASOLINE)»(ref-153402-S19914623502003040400000).

1. Release fuel system pressure. See «FUEL SYSTEM PRESSURE RELEASE (GASOLINE)»(ref-153402-S34229557402003040400000) .
2. Drain the fuel tank. See «FUEL TANK DRAINING»(ref-153402-S12539899082003040400000) .
3. Raise and support vehicle.
4. Disconnect the quick-connect fittings at the fuel filter and the fuel return pipe. See «FUEL LINE QUICK CONNECT FITTINGS»(ref-153402-S13027093362003040400000) . Cap the fuel lines to prevent possible fuel system contamination.
5. Remove the rubber exhaust hangers. Allow the exhaust system to rest on the rear axle.
6. Remove the exhaust heat shield.
7. Loosen the fuel filler hose clamp at the fuel tank.
8. Disconnect the fuel filler hose from the fuel tank.
9. Disconnect the Evaporative (EVAP) emission vapor pipe from the EVAP canister.
10. Disconnect the electrical harness from the multi-pin rear body connector and fuel strap.
11. With the aid of an assistant, support the fuel tank. Disconnect the fuel tank retaining straps.
12. Lower the fuel tank.
13. If cleaning or replacing fuel tank, remove the fuel sender assembly from the tank. See «FUEL SENDER ASSEMBLY»(ref-153402-S21570549432003040400000) . To clean tank, see «FUEL SYSTEM CLEANING»(ref-153402-S19327330872003040400000) .

Scheme 23