BCdawg57

iTrader: (1)

For those of you who don't know, i swaped in a 94 lt1 into my 91.
The other day i tried for my first start and nothing. I smelled all my spark plugs and they all smelled like fuel, so for right now im not worrying about that. I am not getting any spark. I am not getting any spark at the coil either, i tested this by doing the plug wire trick right from the coil and nothing.

Now i tested everything for power and everything has the proper voltage
I did this opti and spark test http://shbox.com/1/4th_gen_tech2.html#opti_test. and discovered i am not getting any AC voltage when the motor is being cranked. Now i realize this means either i missed something retardedly easy right infront of my face, or that the opti, pcm, or any of the wiring between is bad.

The opti is a brand new ac delco unit. the opti harness is off the original motor, i tested the resistance on all the wires and got 0 ohms on all 4. The wiring harness is brand new from speartech. The pcm is off the original car.

I talked to vince @ trifecta cause he did my tune, and he said his tuner can double as a scaner. I tried to pull the codes from the pcm and it gave me an error message. I tried this 20 times 20 different ways and i always got the same result. However his tune uploaded fine to the pcm.

I need to know if there is a way to test the opti for a pulse in the wiring BEFORE it goes through the PCM and back to the ICM. I cant eliminate the pcm or opti based on the test i ran it could be either one.

Anyone has any advice that would be a great help.

Thanks

bingo

iTrader: (2)

Have you had the ICM tested? I assume you checked all the ignition grounds. Have you ohmed out the coil? These are things to check if you haven't.

Klortho

There is a pink ignition wire that is hot on run that enables the coil, might want to check that.

TexasLT1

that's what I was just about to post, to check and make sure all of the power and ground connections are good

BCdawg57

iTrader: (1)

I had the ICM tested. It tested out ok. The pink wire has voltage, everything that should have voltage does, as far as i know.

I was able to retrieve a code today though, code 42, and it said something like ignition circuit grounded.

bingo

iTrader: (2)

Did you check the ground on the head? It will cause a car not to start.

BCdawg57

iTrader: (1)

ground on the head?

All my grounds are on the firewall.

bingo

iTrader: (2)

LT1s have a ground right beside the ignition module to the block. It is a major ignition ground. There is a pic on shoebox's site.

BCdawg57

iTrader: (1)

i have an aftermarket harness from speartech, and there was only 1 ground on the harness and it is on the firewall along with all the other grounds and the chasis to block ground.

bingo

iTrader: (2)

Have you verified that all of your grounds(black/white stripe) are good grounds? There was also a bad batch of AC Delco optis a while back. You might want to also look into this.

BCdawg57

iTrader: (1)

I will verify all my grounds, and the wires between my pcm and icm, and if those are all good i am going to send my pcm to vince @ trifecta to have it tested. I understand these pcms rarley go bad, but ive never witnessed this on a running car and everything else is new..

BCdawg57

iTrader: (1)

I checked all the wires, they were good. I pulled the codes again and it looks like 42 was intermittent. I got the wonderfuly exciting code 16. Brand new opti is no good. that really sucks. Is there ANY reason other than the opti i could get this code? Like faulty plugs wires or anything like that?

bingo

iTrader: (2)

The only thing I can think of is a bad connection to the opti. Do you have another opti you can try?

BCdawg57

iTrader: (1)

i got my opti from thepartsladi on ebay and i was informed to just send mine back and he would replace it with a new one. But i found this that might help me narrow it down a bit:
ill let ya know how that turns out