Fuel Pressure Regulator: Testing and Inspection

1. Check that battery voltage is at least 12 volts.
2. Disconnect battery negative terminal.
3. Remove fuel delivery pipe between Cold Start Injector and fuel rail. Use caution if the fuel system is still under pressure.

Disconnecting Cold Start Injector Fuel Pipe:

4. Connect a suitable fuel pressure gauge to the fuel rail using the union bolt and gaskets to provide a tight seal.

Connecting Fuel Pressure Gauge:

5. Wipe off any gasoline that may have escaped when the fuel pipe was disconnected and reconnect negative battery terminal.
6. Start the engine and observe the fuel pressure gauge readings at idle.

Fuel Pressure: 30 - 33 PSI (206 - 226 kPa)

7. If pressure is low, check fuel pump output and/or fuel filter for restrictions. If pressure is high, continue checking FPR.
8. Disconnect vacuum sensor hose to FPR and observe gauge readings.

Testing Fuel Pressure With Gauge - Vacuum Disconnected:

Fuel Pressure: 38 - 44 PSI (265 - 304 kPa)

9. If fuel pressure does not change, check the vacuum hose for blockage. If no problems are found with the vacuum hose, replace the FPR. Refer to COMPONENT REPLACEMENT AND REPAIR PROCEDURES.
10. Reconnect the vacuum hose and check that fuel pressure reading returns to pressure noted in step 6.

Testing Fuel Pressure With Gauge - Vacuum Connected:

11. If fuel pressure does not drop, replace the FPR.
12. Stop the engine and disconnect the fuel pressure gauge from the engine.
13. Reinstall the fuel delivery pipe to the Cold Start Injector.
14. Wipe off any gasoline that may have escaped when the fuel pipe was disconnected.
15. Start the engine and check the Fuel Rail for cracks or signs of fuel leakage, especially around the fuel injectors.