P0268

Diagnostic Chart:

Schematic:

The fuel injection system on both SOHC and DOHC engines utilize sequential fuel injection. The PCM independently controls each fuel injector through separate internal drivers. The PCM drivers hold each fuel injector circuit to ground for a certain length of time based on engine operating parameters. The fuel control system is designed to maintain a 14.7 to 1 air/fuel ratio under all conditions except in power enrichment mode (heavy acceleration/heavy engine load). The PCM monitors the fuel injector circuits for low and high voltage faults. DTC P0268 sets when fuel injector #3 is being commanded On and the feedback voltage at the PCM is high.

DTC PARAMETERS
DTC P0268 will set if fuel injector #3 voltage is greater than 1.25 volts when fuel injector #3 is being commanded On.

DTC P0268 diagnostic runs continuously with engine running.

DTC P0268 is a type D DTC.

DIAGNOSTIC AIDS
To locate an intermittent problem, start engine and use Scan tool to monitor INJECTOR 3 - HIGH VOLT test. When a fault (short to voltage or shorted solenoid) exists, the Scan tool will display TEST FAIL.

The test will fail only when the device is being commanded On and the voltage at the PCM is high. The test updates every 100 ms whenever the ignition is turned On and the device is being commanded On via the Scan tool or PCM.

Fuel injector resistance: 12.2 ±0.4 ohms at 74°F