LB7 Fuel Pressure Relief Valve Shimming Instructions

1. Remove the air intake pipe.
2. Disconnect the air conditioning (A/C) compressor clutch electrical connector.
3. Disconnect the A/C cut out switch electrical connector.
4. Remove the drive belt.
5. Remove the A/C compressor bolts.
6. Move the A/C compressor with the hoses attached to the right side of
the engine compartment.

7. Drain about 3/4 gallon of coolant. Remove the water outlet tube.
8. Disconnect both main harness electrical connectors.

9. Remove both main harness electrical connector to bracket bolts (1).
10. Remove the main harnesses from the bracket.

11. Disconnect the engine coolant temperature (ECT) sensor electrical connector (1).

12. Disconnect the barometric pressure (BARO) sensor electrical connector (1).

13. Disconnect the glow plug relay electrical connectors (1,2,3).

14. Disconnect the fuel rail temperature sensor electrical connector (1).

15. Disconnect the left front fuel injector electrical connector (1).

16. Disconnect the left rear fuel injector electrical connector (1).

17. Disconnect the fuel pressure regulator electrical connector (1).

18. Disconnect the oil level sensor harness electrical connector (1).

19. Remove the positive crankcase ventilation (PCV) hose from left valve cover.

20. Pull up and to your left the wiring harness to gain access to the block
which holds the FPRV.

A view of the block with the turbo inlet and harness out of the way.

21. Remove the banjo bolt (#1) on your left side that holds the return
lines to the FPRV (19mm bolt?).
22. Loosen the 3 high pressure lines (#3) and the high pressure line on the CP3.
23. Remove the 2 nuts (#2) and clamp holding down the block and a fuel line
that has to be moved.
Refer to the above picture to see a fuel line disconnected. You may need to
remove or loosen some clamps so the line will move enough.

Down inside the hole the bolt went into is a plug with a 5mm allen hole (2nd photo).
Put the block in a vise. Look down into the hole and remove the plug with a 5mm
allen wrench. The shim OD is .372, ID is .20, and thickness is questionable. After
researching the PPE shim kit, I have found the shim is .20 thick. I only used a #8
flat washer ground to about .372 OD to fit into the plug to put more compression
on the spring. Return fuel comes through the holes.

This small shim did not fix the P0093 code. It's possible that the shim was too
small or that the FPRV is fine and the CP3 is weak. The PPE kit calls out for 2
of the included shims to be used but this kit is not intended for an LB7.