DTC Troubleshooting: P1066 (95)
DTC P1066:
 Fuel Rail Pressure Higher Than Expected
NOTE: Before you troubleshoot, record all freeze data and review the general troubleshooting information.
  1. Turn the ignition switch ON (II).
  1. Clear the DTC with the HDS.
  1. Do the FUEL RAIL PRESSURE TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES -
Go to Step 4 .
NO -
Replace the fuel supply pump assembly, then go to Step 5 .
  1. Do the FUEL PRESSURE CONTROL VALVE TEST in the INSPECTION MENU with the HDS.
Is the result OK?
YES -
Intermittent failure, the system is OK at this time.■
NO -
Replace the fuel supply pump assembly, then go to Step 5 .
  1. Turn the ignition switch ON (II).
  1. Reset the ECM with the HDS.
  1. Start the engine. Hold the engine speed at 2,000 rpm (min −1 ) with no load (in neutral) until the radiator fan comes on, then let it idle.
  1. Check for Temporary DTCs or DTCs with the HDS.
Is DTC P1066 indicated?
YES -
Check for poor connections or loose terminals at the FRP sensor, the fuel supply pump assembly, and the ECM, then go to Step 1 .
NO -
Troubleshooting is complete. If any other Temporary DTCs or DTCs are indicated, go to the indicated DTC's troubleshooting.■