my ss is stalling out and its throwing a P1351 code( ingintion control curcuit voltage high). Has anyone had this problem before and if so what action did you take to fix it....

after doing some online research the 1351 code is actually P1351 Ignition Coil Control Circuit High Voltage. so im guessing that it has nothing to do with the opti. My car will not start at this time, but has started before and stalled after only ruuning a few minutes. i was getting ready to replace the opti, but i was wondering if its the coil that needs replacing or its a ground issue. Any feed back would be very helpful before i start hanging parts i dont need.

 

Your problem is on the White wire going between the PCM and the ICM. The first thing to do is clear the code and actually measure the voltage on the white wire during engine cranking. Even watch it while the engine is running (if you can get it running).

Normally this white wire will be between 0.5 and 4.5 volts. Yours is going above 4.6 volts. If it's close to 12 volts, that means the white wire is shorted some were to battery voltage. That would be easy to find.

Your problem should be either the wire or the ICM. The last alternative is not good.

 

problem fixed.....it was the icm....i swapped out that autozone p.o.s. with a gm icm that i had laying around...put it and bam car started rightup and has not die yet...code cleared and the car is idling better than before.

 

I am having a very similar issue, Same code posting p1351 Ignition control circuit high voltage. But my car does not die. I replaced the alternator, Ignition control module, opti and opti harness. I was curious about the white wire with diagnosing it and thought i should just replace the entire harness. I would like to avoid replacing the harness sooo any other suggestions you can offer would be nice ty.


PS
I have an 1996 camaro 5.7 LT1 if that makes any difference.

 

got another one of them ICM's from GM laying around lol

 

Have you cleared the code to see if it returns? Have you looked at the signal on the white wire? What is the level it is going to?

What about the ICM you just installed????? What brand is it? Did you have the same problem before you installed it?

 

I bought the ICM Master Pro Ignition - Igniter Part Number: 2-7137 from O'reilly AKA Kragen auto parts because of the numerous altercations i have had with autozone.. Bah! I did not have to clear the code. When i installed the ICM and alternator the code cleared itself. I thought i had fixed it with the new alternator and ICM both. It got up the operating temp and then posted again. It is acting the same way as before the new ICM. I havent had time to go through my book to check the wire yet, but i will when i have time this afternoon.

 

I tested the white cable that now looks yellow from age lol.

the images below show how i tested and what wires i am testing and what selection on the meter i used.

 

Your meter is set to look at a diode. You are measuring from the white wire to the black ground wire. The meter is set incorrectly however you are checking to ground and that is not your problem. That is, your white wire is not shorted to ground. If it were, you would want to measure the pins your are showing with the meter set to 200 ohms. Right above the orange on/off button.

What you want to do is set the meter to AC volts just to the left of where you are. Plug the connector back in and while the engine is running, measure from the white pin with the red meter lead to a good ground with the other meter lead. It should be reading less than 4.6 volts. You will have to back probe the connector.

 

I am going to take the car to a couple of professional electricians for vehicles to see if they can shine some light on the subject. I was told the car was chipped also, but i am not sure where the chip is located. I don't need someone taking my chip.

 

There is no replaceable "chip" in a 96 LT1 PCM. Some people call the "module" that plugs into the PCM harness connectors, like the one from Hypertech, "chips". If that's what you've got, you'd be better off if someone took it.

Not sure why you didn't just follow Speed's advice and check it yourself.

 

well, i am better off placing someone else responsible for fixing the part "they" messed up rather than having to put more money into a problem that i could watch a pro do then learn from myself as i watch them work on the vehicle. Further more i will post my "Chip/Module" specs when i find out if the modification goes in the PCM or the ECM.

i just want to know if it goes into the PCM or ECM.. I guess i will have to shop and look for all the places manufacturers design them to be installed instead of getting a simple answer.. at least speedy is nice patient and willing to let me keep the parts i already have rather than just deciding to "ditch" what is working just fine now.. the problem lies in the wire.. i just want to know positioning.. sorry if i offended you sir.

 

You didn't mention that anyone other than yourself replaced anything. Nor did you mention if it was before or the result of the problem. We don't know anything about "they" but can tell you this. Unless they have ample experience with LT1's, you could be wasting your time.

One last point. If it was a "hard" code, it would have disabled the engine. So it's likely the wire is too close to something that might carry high ignition voltage. Also, I believe the PCM only looks at the condition of the white IC wire voltage during cranking and not while it is running.

Incidentally, if you had a plug in module such as was mentioned before, it would be plugged in at the PCM and should be obvious if it was there.

At this point you should abandon this post and start your own if further "ideas" are necessary.

 

So, who "messed up"? And how did they accomplish that? Would make it a lot easier to know all the facts up front.

You only have a PCM (Powertrain Control Module). The "ECM" is the name for the "Engine Control Module" used in place of the PCM in the 93 LT1's only.

Sorry I offended you.... but it is evident now that you didn't even both to provide all the info up front. And, it appears you are a little fuzzy on the module.

I won't offend you any more. I'll let someone else help you.

Good luck.