Diagnostic Aids

Check for any of the following conditions:

• Water, contaminated fuel, or inferior quality fuel can cause a no start or hard start condition even though the fuel injectors and circuitry are okay.
• Check for a faulty spray pattern from the fuel injector nozzle if both the fuel injector solenoid and the fuel injector circuit are okay.
• There may be fuel spray at the fuel injectors and the indicated fuel pressure may be correct, yet there may not be enough fuel to start the engine. If the fuel injectors and the injectors' circuit are okay, and fuel spray is detected, some fuel injector nozzles may be partly blocked or restricted. If PCM receives incorrect inputs from the various information sensors, the fuel delivered by the fuel injectors may be inadequate to start the engine. Check all engine data parameters with a scan tool and compare the values indicated with expected values or values on a known good vehicle.
• The normal fuel injector resistance is 13.4-14.4 ohms at 68°F (20°C).
• If you were sent here by DTC P0300 and all the injectors checked okay, the MISFIRE CURRENT CYLINDER or MISFIRE GRAPHIC information on a scan tool can be used to determine which injector circuit should be examined more closely.

An intermittent malfunction may be caused by a fault in the fuel injector electrical circuit. Inspect the wiring harness and the components for an intermittent condition. See INTERMITTENTS in TROUBLE SHOOTING - NO CODES - 1.8L VIBE article.