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Fuel Pressure: Testing and Inspection

NOTE: TestBook can be used to activate fuel pump for these tests, otherwise use procedure below.

1. Disable ignition system.

2. Locate and remove fuel pump relay RL12.





3. Install fused jumper wire (or momentary contact switch) between terminal 3 and terminal 5 in the relay socket.

4. Install fuel pressure gauge on fuel rail.

5. Activate fuel pump, and take fuel pressure reading.

Fuel pressure should be 2.3 - 2.62 bar (33.8 - 38.5 psi).

6. Apply a vacuum of at least 381 mm Hg (15 in Hg) to fuel pressure regulator.

Fuel pressure should drop to 1.9 - 2.0 bar (26-28 psi).

7. Shut OFF fuel pump, and observe pressure.

Pressure should not fall more than 0.7 bar (10 psi) in one minute.

8. Locate and remove the fuel return pipe from the fuel pressure regulator, and install a hose on the pipe nipple.

9. Turn ON fuel pump. Allow fuel to discharge into a graduated receptacle.

Fuel volume should be at least 0.7 Litre (25 oz.) after 25 seconds.

10. If volume and or pressure are below specification, the fuel filter may be clogged.