Check Crankshaft Pulley
On models equipped with crankshaft pulley-mounted pulse ring, check crank pulley and pulse
ring for damage or looseness. On models not equipped with crankshaft pulley-mounted pulse ring, remove front cover if necessary. Check crank pulley and pulse ring for damage or looseness. On all models, repair as necessary.
1) Check Injector Driver PIDs
Turn ignition on. Using scan tool, select and record appropriate injector PID for suspect injector. If injector PID value indicates YES, go to next step. If injector PID value indicates NO, go to step 3).
2) Check Fuel Injector & Circuit Resistance
Turn ignition off. Disconnect PCM 104-pin connector. Inspect connector for loose, damaged or corroded terminals. Repair as necessary. Measure and record resistance between suspected fuel
injector pin and pin No. 71 (VPWR) at PCM connector. If resistance is 11-18 ohms, replace PCM. If resistance is not 11-18 ohms, check wiring
3) Check Fuel Pressure
Turn ignition off. Release fuel pressure Install fuel pressure gauge. Start engine and allow to idle. Note fuel pressure gauge reading. Increase engine speed to 2500 RPM and maintain for one minute. Note fuel pressure. If fuel pressure is 80-120 psi (552-827 kPa) on Natural Gas vehicles or 30-60 psi (207-413 kPa) on all other models. If fuel pressure is not as specified, check and repair fuel system as necessary.
Wednesday, February 11th, 2009 AT 10:00 PM
