im still not sure on the duty cycle, but i did check the injection pulse by putting a light in the inj. plug and crack the engine. the light looked like a strobe light with irregular pauses. so i then checked the CMP connector. now i was told 1 wire is ground, 1 is signal (no power), and 1 has 5 volts (with key on). i have 1 grd. and both wires have 5.2 volts. so i followed the wires back and found the sig. wire and the AC comp. power wire were rubbing together. i repaired both wires and still have the same problem. i followed the CMP sig wire back to the PCM and cut the wire to see if the pcm was sending out voltage, and it is, 5.2 volts. am i right on the signal wire should have 0 volts? and does this mean my pcm needs replaced? sorry so long

 

You should not have 5 volts on the CMP Signal. If you do then you have a short to the 5 volt ref. So you cut the Sig wire at the ECM and still get 5 volts ? If yes ECM is done.

 

so you believe i need a new ECM? do you know of anywhere that i can get one? i bought this truck with this problem, (i know you can laugh but i got a good deal) the guy i bought it from rebuilt the motor, you dont think it could be a damaged cam sensor ring? i order it and can pick it up in the morning, but i never paid for it yet.

 

sorry didnt read your question right. i did cut the signal wire at the pcm and i do get 5 volts coming out of the pcm.

 

Just to be clear the cam sensore has three wires

1 DB/GY CMP SIGNAL (from Sensor to ECM) is this the wire you cut and got 5 volts on the ecm side ? If yes ECM is shorted internally.

2 DB/DG SENSOR GROUND

3 YL/PK 5 VOLT SUPPLY (from ECM to Sensor)

You can get on at a junkyard or check with your local parts store too as they sell remaned units. Just make sure its the same Part Number.

 

thanks for all your help, ill try to order one this weekend.

 

Check this out.

For the cam sensor, have you tried checking the resistance?

 

Wont matter as he says he cut the sig wire at the ECM and got 5 volts at the ECM side of the wire.

Most likely the short to the A/C clutch wire killed the ECM.

 

ok i finally got my new ecm today. and the truck is still doing the same thing? i went thur the whole engine harnes to check for anymore bad wires, and everything looked good. i did pull all 6 plugs out and hooked the coils to them, just to watch how they spark. and the driverside of the motor (all 3 plugs) seems to sparking at the same time. im lost