Low Pressure Lock-Off (LPL) Solenoid Replacement

LOW PRESSURE LOCK-OFF (LPL) SOLENOID REPLACEMENT

TOOLS REQUIRED
J 45878 Combustible Gas Detector

REMOVAL PROCEDURE
1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief Procedure.
2. Disconnect the negative battery cable.

CAUTION: Refer to Battery Disconnect Caution in Service Precautions.




3. Disconnect the low pressure lock-off (LPL) solenoid electrical connector (5).
4. Disconnect the fuel inlet line (1) from the LPL fitting (2).




5. Remove the intermediate pressure regulator (IPR) fuel outlet line hold-down nut (6).
6. Remove the fuel outlet line hold down (4).
7. Disconnect the IPR fuel outlet lines (5, 8) from the IPR (2).




8. Remove the IPR/LPL bracket nuts (3).
9. Remove the IPR/LPL assembly from the vehicle.




10. Remove the bolts (3) that retain the IPR/LPL assembly (1, 4) to the bracket (2).




11. While holding the line union (2) rotate and remove the IPR (3) or the LPL (1) as required.

INSTALLATION PROCEDURE




1. While holding the line union (2) rotate and install the IPR (3) or the LPL (1) as required.

IMPORTANT: Apply pipe thread sealant with Teflon(R) to the threads of the line union (2). Do not use Teflon(R) tape.

Tighten the IPR or LPL hand tight plus one to three turns as required to align the IPR/LPL assembly to the bracket.




2. Install the IPR/LPL assembly (1, 4) to the mounting plate (2) using the attaching bolts (3).

NOTE: Refer to Fastener Notice in Service Precautions.

Tighten the bolts to 12 N.m (9 lb ft).




3. Install the IPR/LPL bracket (4) to the engine (2) using the attaching nuts (3).

Tighten the nuts to 12 N.m (9 lb ft).




4. Connect the IPR fuel outlet lines (5, 8) to the IPR (2) using new O-rings (3). Lubricate the O-ring with petroleum jelly.
5. Install the line hold-down bracket (4) and nut (6).

Tighten the nut to 9 N.m (80 lb in).




6. Connect the LPL electrical connector (5).Connect the fuel inlet line (1) to the LPL fitting (2) using a new O-ring face seal. Lubricate the O-ring with petroleum jelly.

Tighten the fitting to 37 N.m (27 lb ft).

7. Install the negative battery cable.

CAUTION: Refer to Battery Disconnect Caution in Service Precautions.

8. Start the vehicle and inspect for CNG fuel leaks at the serviced fitting using the J 45878 or an equivalent liquid leak detector.