Fuel Pressure Regulator: Service and Repair

Model R620 Fuel Rail Assembly:

REM0VAL
1. Disconnect the negative battery terminal.
2. Relieve the fuel system pressure. Refer to Fuel System and Air Induction / Service and Repair.
3. Remove the intake manifold plenum.
4. Remove the fuel rail assembly.
5. Remove the pressure regulator bracket attaching screws and pressure regulator mounting bracket.
6. Disconnect the hand fuel rails from pressure regulator base.
7. Disconnect the base to rail connectors from regulator base, or rails.
8. Remove the connector O-rings from base to rail connectors and discard.
9. Remove the fuel return O-rings from fuel rails and discard.

INSTALLATI0N
1. Lubricate the new fuel return O-rings with engine oil, and install on fuel rails. (Fuel return O-ring is larger in diameter than the connector O-ring).
2. Lubricate the new connector O-rings with engine oil, and install on base to rail connectors.
3. Install the base to rail connectors into the regulator base.
4. Connect the left and right hand fuel rails to the regulator base.
5. Install the pressure regulator mounting bracket and torque the screws to 3.2 Nm (28 lb in.)
6. Install the fuel inlet fitting in the regulator and torque to
48 Nm (35 lb ft.)
7. Install the fuel outlet fitting in the regulator and torque to
40 Nm (30 lb ft.)
8. Install the fuel rail assembly.

Inspection
^ Temporarily connect the negative battery terminal.
^ Turn the ignition switch to the "0N" position for two seconds, then turn to the "0FF" position for ten seconds. Again turn to the "0N" position and check for fuel leaks.
^ Disconnect the negative battery terminal.

9. Install the intake manifold plenum.
10. Connect the negative battery terminal and tighten the fuel filler cap.

NOTE: The Electronic Control Module (ECM) will need to relearn the Idle Air Control (IAC) valve pintle position following battery reconnection. This procedure allows the ECM memory to be updated and provides for a stable idle speed.

Idle Learn Procedure
1. Install the Tech 1 "SCAN" tool.
2. Ignition "ON" engine "OFF".
3. Select the "IAC SYSTEM", then "IDLE LEARN" in the "MISC. TEST" mode.
4. Proceed with the idle learn as directed by the Tech 1 "SCAN" tool.