DTC Troubleshooting: P1086 (95-6)

DTC P1086:  Fuel Rail Pressure Control Valve Malfunction

1.Turn the ignition switch ON (II).

2.Clear the DTC with the HDS.

3.Do the FUEL RAIL PRESSURE TEST in the INSPECTION MENU with the HDS.

Is the result OK?


YES - Go to 4.


NO - Replace the fuel supply pump assembly, then go to 5.


4.Do the FUEL PRESSURE CONTROL VALVE TEST in the INSPECTION MENU with the HDS.

Is the result OK?


YES - Intermittent failure, system is OK at this time.n


NO - Replace the fuel supply pump assembly, then go to 5.


5.Turn the ignition switch ON (II).

6.Reset the ECM with the HDS.

7.Start the engine. Hold the engine speed at 2,000 rpm (min-1) without load (in neutral) until the radiator fan comes on, then let it idle.

8.Check for Temporary DTCs or DTCs with the HDS.

Are any Temporary DTCs or DTCs indicated?


YES - If DTC P1086 is indicated, check for poor connections or loose terminals at the fuel rail pressure control valve and the ECM, then go to 1. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.


NO - Troubleshooting is complete.n