Hello, I have a major headache, and I am majorly confused with my 96 monte 3.4 mtr. I just swapped the engine out, because it was tapping and had the RPM gauge bouncing all around...but the motor never increased RPM. I changed the wiring harness, new alternator, starter, Crank sensor (both), cam sensor, and ignition module. I had a good 12v to the module, and that crank sensor in the side of motor has good ohms and AC volts, but I still have no spark out of any of the coil packs. I swapped the entire module out with the one on my grand-am (the currently running vehicle), and I have the same scenario....NO SPARK! Is this a common problem or a rare case? I can't find too much about it online. Any thoughts would be greatly appreciated....

Thanks,
Brent

 

hmmm so the problem is no spark.

the areas to look are:
-the ICM (ignition control module) which it sounds like you swapped with a known good module.
-PCM. do you have a code reader? does it interface with the car? the pcm could be bad.
-PCM fuse or ignition fuses and relays. take them out clean them and reinstall.
-VATS. is the security light on?
-check that power is making its way to the
this is not an issue i have ever had on my DOHC engine.

so the engine you swapped in had all different sensors and harness then the one you had before or did you reuse anything? what ever wasnt changed i would look at those as an RPM issue from the old engine could cause the ICM not to fire.

where are you? maybe there is someone in your area that can come and help. im in florida.

 

Thanks for the response phoenix, and sorry for the delay

-The engine I put in had identical sensors, but I bought brand new ones to be safe.
-I checked at the computer and found out that as soon as I try to start the car, the 12V on the negative wire at the ECM becomes 0 when trying to start.
-The VATS security light is steady on the dash inside the car, and does not blink.

I have found out that the 15amp ECU fuse on the passenger side is now starting to "blow" every time switched to the "on" position. I rechecked to make sure my grounds are ok and that no power is hitting ground...all good.

I do not have a tech 1 scanner, just a OTC OBD2/1 and a actron code connect scanner from advance. But from what I can get from the car, P1655, P1652, P1642 is the only "constant" codes I have. Which in repsect, those codes do not present a "no spark" condition.

Figuring that all the sensors on the motor have been changed on the motor to new ones, ( i do understand that not everything "new" is going to work), and that the ECM loses the ground and blows the 15amp fuse. Is the question a short to power in a harness/ECM, or a short to ground in the harness/ECM?? Figuring the RPM issue is a sensor.

I live in Pittsburgh, PA.