P0088

P0088-FUEL RAIL PRESSURE SIGNAL IS ABOVE MAX LIMIT





For complete wiring diagrams refer to Diagrams/Electrical.


- When Monitored:

Engine running.

- Set Condition:

Fuel pressure is above a calibrated value for a calibrated amount of time.







Always perform the Pre-Diagnostic Troubleshooting procedure before proceeding.

Diagnostic Test


1. FUEL PRESSURE SENSOR

Using the scan tool, compare the scan tool reading for fuel pressure set point to the scan tool reading for actual fuel pressure.

Does the actual fuel pressure correlate with the fuel pressure setpoint while operating the engine over various operating conditions?

Yes

- Go To 2

No

- Check the electrical connector of the Fuel Control Actuator, if the connection is tight, replace the fuel control actuator.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

2. FUEL PUMP

Turn the ignition on.

Disconnect the Electronic Fuel Control Actuator connector.

Connect an incandescent test light across the Fuel Control Actuator driver pin and the Fuel Control Actuator return wire at the fuel control actuator connector.

Observe the test light.

The ECM will perform a self test of the circuit which should momentarily flash the test light brightly, one time, approximately 20 seconds after being connected.


NOTE: Compare test light brightness to that of a direct connection to the battery.

Did the light flash brightly?

Yes

- Replace the fuel pump.
- Perform POWERTRAIN VERIFICATION TEST. Powertrain Verification Test

No

- Refer to the INTERMITTENT CONDITION Diagnostic Procedure. Intermittent Condition