Fuel Pressure Regulator Replacement 5.3L (L59) Engine

Important: The fuel pressure regulator retaining clip is specific to the fuel rail-regulator design and cannot be interchanged.

1. Relieve the fuel system pressure. Refer to Fuel Pressure Relief .
2. Remove the fuel pressure regulator vacuum hose.
3. Clean any dirt from the fuel pressure regulator retainer and surrounding area.
4. Remove the fuel pressure regulator retainer (8).
5. Remove the fuel pressure regulator (9).
6. Ensure none of the following parts are still in the fuel rail.

•	Backup ring (10)

•	Regulator seal O-ring (11)

•	Regulator filter (12)

•	Regulator seal O-ring (13)

1. Ensure that the NEW fuel pressure regulator retainer is the correct one.
2. The tab (1) is used on the E85-straight vacuum port retainer (3).



3. 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)

4. Lubricate the fuel pressure regulator O-rings (11, 13) with clean engine oil.
5. Install the fuel pressure regulator (9).

Important: Whenever the fuel pressure regulator is removed from the fuel rail NEW O-rings and a NEW retaining clip should be used on reinstallation.

6. Install the NEW fuel pressure regulator retainer (8).
7. Install the fuel pressure regulator vacuum hose .
8. Install the fuel fill cap.
9. Connect the negative battery cable. Refer to Battery Negative Cable Disconnection and Connection in Engine Electrical.
10. Use the following procedure in order to inspect for leaks:

10.1.

Turn the ignition ON, with the engine OFF, for 2 seconds.

10.2.

Turn the ignition OFF for 10 seconds.

10.3.

Turn the ignition ON, with the engine OFF.

10.4.

Inspect for fuel leaks.