Ok so here it is a 2000 chevy impala 3.4l that has no spark. Have checked the crank,cam,coils,icm,and power to the icm 4 times and all is good. Now I have replaced the ignion switch 2yrs ago after a lock up. The sercrity light is not flashing after cranking. The car did start to die only in drive and at a stop. As soon as gas was applied it ran great. Was thinking tps sensor befor wife got home and then the next morning would not start. So I really hate this car and want to shoot it many many times but my wife loves it and does not want anything else..Any help would be great thanks ..

 

Welcome to the forum. You get "no spark" from all the spark plugs? Is that "crank" the CKP sensor you speak of? Which one, 7X or 24X, and how did you check it? Same for the ICM, how did you check it and is it getting power while you're cranking the engine?

 

Thankyou for the welcome.. Ther is no spark to all plugs or wires from the coil packs as I have a spark tester and tryed at the plugs and the coils. I check the ckp sensor at the icm with a scope and watched the pulse and it was cranked over. As for the ICM I took it to autozone and had them check it. All sensors have been check by me 4 times and others have check just to make sure I was doing it right.

 

Okay, then, is the PCM asserting the BYPASS signal, i.e., 5V at ICM terminal A, TAN/BLK wire? If so, the PCM should also pulse in the IC CONTROL signal at ICM terminal B, WHT wire. Also, is there any trouble codes, current or historical?

 

If the 7x cps is bad, it will not start, and probably won't give you a code. You said you checked it, how did you check it? I take it out, with an ohm meter you should have around 1K, it also has a magnet in it (basically a mag pickup).

 

I have checked the sensors with a scope a a tec 2. I have watched the pulse with both and has been good. I can see that it is seeing cranking eng speed but no ingion advance while cranking. Just done replacing the icm just for a maybe and still nothing...

 

What was the amplitude?