Low Pressure Regulator (LPR) Replacement

TOOLS REQUIRED
J 41416 Ultrasonic Leak Detector

REMOVAL PROCEDURE

CAUTION:
^ Refer to Compressed Natural Gas (CNG) Flammability Caution in Service Precautions.
^ Refer to Compressed Natural Gas (CNG) Fuel Pressure Relief Caution in Service Precautions.




1. Relieve the CNG fuel system pressure. Refer to the Fuel Pressure Relief Procedure.

CAUTION: Refer to Battery Disconnect Caution in Service Precautions.

2. Disconnect the negative battery cable.
3. Remove the engine cover.
4. Disconnect the fuel line (6) at the LPL fitting (5).
5. Disconnect the LPL connector (4).




6. Remove the spring clamp from the fuel outlet hose (5) at the LPR fitting.




7. Disconnect the idle control solenoid hose (6).
8. Disconnect the fuel control solenoid hose (5).
9. Disconnect the LPR reference hose (1).
10. Remove the mounting bolts (2).
11. Remove the LPR from the vehicle.
12. Remove the low pressure lock-off solenoid and bracket from the LPR if necessary.




13. Remove the LPR bracket (2) ruts (1) if bracket removal is necessary.

INSTALLATION PROCEDURE




1. Install the LPR bracket (2) onto the intake manifold (3) studs if necessary.

NOTE: Refer to Fastener Notice in Service Precautions.

2. Install the LPR bracket nuts (1).

Tighten
Tighten the nuts to 11 N.m (97 lb in).




3. Install the low pressure lock-off solenoid and bracket to the LPR if necessary.
4. Place the LPR onto the engine bracket.
5. Install the mounting bolts (2).

Tighten
Tighten the mounting bolts to 12 N.m (106 lb in).

6. Connect the LPR reference hose (71).
7. Connect the fuel control solenoid hose (5).
8. Connect the idle control solenoid hose (6).




9. Install the spring clamp to the fuel outlet hose (5) at the LPR fitting.




10. Connect the fuel line (6) at the LPL fitting (5).

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

11. Connect the LPL connector (4).
12. Connect the negative battery cable.
13. Prime the CNG fuel system by cycling the ignition ON and OFF several times.
14. Start the engine and use the J 41416 in order to inspect for CNG fuel system leaks at each serviced fitting.
15. Inspect for proper coolant level and fill as necessary.