new tune new problems
Thread Starter
Staging Lane
Joined: Jun 2012
Posts: 75
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From: sac
new tune new problems So I did as alot of you said and got the pcmforless tune. Real quick recap. Before tune car drove until warmed up then died let it cool it would fire right back up. Got the tune and the check engine light was still on for some reason. Took car out to a video shoot for friends song did a few donuts car ran fine. On the way home it dies and won't fire back up at all. Before tune I have recently put new plugs opti icm and coil. Could this issue be bad o2 sensors all along? I'm real tired of stupid little issues causing such a big headache. PLZ HELP!!!
Thread Starter
Staging Lane
Joined: Jun 2012
Posts: 75
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From: sac
Ok so had coil and icm checked its not the icm there saying no reading on coil but I don't think they read it right. Every time I go check my coil they say they can't get a reading. Any other solutions to my problem.
I'm not 100% sure, but I don't think having them test the icm would let you know that it is getting heat soaked. If it was a heat soak problem, then the problem would only occur after the engine has been running for a bit and had time to soak the icm, or if you shut the engine off for a bit and your engine heat soaks which would in turn soak the icm.
Testing the icm when cold would then yield results saying it's fine, but when it heats up because of the engine the malfunctions start to happen. See what I'm trying to say?
Reinstall the icm, space it from the head with washers, and see if that solves your problem.
Maybe you already tried this, but going off your posts, you only took the icm in to test it and never tried installing it and spacing it from the head and seeing if that solved your problem.
Testing the icm when cold would then yield results saying it's fine, but when it heats up because of the engine the malfunctions start to happen. See what I'm trying to say?
Reinstall the icm, space it from the head with washers, and see if that solves your problem.
Maybe you already tried this, but going off your posts, you only took the icm in to test it and never tried installing it and spacing it from the head and seeing if that solved your problem.
Thread Starter
Staging Lane
Joined: Jun 2012
Posts: 75
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From: sac
Correct only took it off will reinstall it and see what happens but it won't even fire so I am waiting to get coil on my way home tomorrow. Could the heat soak of the icm cause my coil to go out. I would say 40 miles ago icm and coil went out at same time now another coil? Its pretty ridiculous I'm trying to get my hands on obd1 reader as we speak
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Staging Lane
Joined: Jun 2012
Posts: 75
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From: sac
Ok so it's not coil or icm. I disconnected battery over night fired it up took it to get code read it died as I was pulling in friends place. The reader is saying there is no codes stored. I can start the car as long as pedal is to the floor. So decided to unplug mass air sensor and the car would run rough at first until I rev it a few times would run ok. Any ways I got it running enough to get it home. Mass air is bad? Is it o2 sensors maybe even the temp sensor. Plz help and thanks. O and I can disconnect a vacuum line and it will run as well
TECH Veteran
Joined: Dec 2008
Posts: 4,147
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From: Little Rock, AR
You need some scan data to see what O2s, MAF, temp sensor, etc. are doing. Disconnecting a vacuum line gives it more air, so sounds like it is running rich. Guessing at what the cause is will get you nowhere.
agreed, you need to get some sort of code reader, live data reader on there to see whats really going on.... make sure there is no wire touching the maf wires that can arc over to the maf like a coil wire... ive read that people had issues with that before, but without a reader at this point your just going to be guessing and throwing parts at it
Thread Starter
Staging Lane
Joined: Jun 2012
Posts: 75
Likes: 0
From: sac
Cause I was doing a rebuild on my car and have it all under warranty. And the icm was bad. Not sure the brand got it from O'Reilly. The obd1 reader wouldn't read and it also reads live data but as said it wouldn't read. Were can I get a cable at to hook up to my lap top and wat is it called. Will it even work done the code reader didn't
orielly sells there own kind of opti, richardson or some crap like that, ask me how i know.... needless to say its garabage, the cap is honestly a really weak point on them, mine had less then 1000 miles on it and was arcing inside the cap causeing a nasty misfire, jsut fied it this weekend.....
Thread Starter
Staging Lane
Joined: Jun 2012
Posts: 75
Likes: 0
From: sac
Can a coolant temp sensor actually cause these type of problems? I know it did get left out and rained on a few times during my rebuild but really can that little sensor cause such a big problem
Three things:
1) Tuning the PCM will never fix a problem like you have.
2) Never take a coil, module, anything like that to a parts store for testing. There is no valid bench-top test for those components.
3) Don't buy anything from Autozone that has a wire going to it. LOL
1) Tuning the PCM will never fix a problem like you have.
2) Never take a coil, module, anything like that to a parts store for testing. There is no valid bench-top test for those components.
3) Don't buy anything from Autozone that has a wire going to it. LOL
!! 
Sounds like a posssible bad connection to me . Had a similar die when hott issue... I finall tracked down the ground pin connection in the opti harness was so perfectly straight in the opti harness to engine harness weatherpack connection that it would randomly loose contInuity once hot and engine would spit ,back fire and die... W/No codes or SES.
I then slightly bent all pins within opti harness, opti, and icm ..hasn't died again since. I also found a poor Harness ground prior to fixing daily constant engine dieing issue.
I then slightly bent all pins within opti harness, opti, and icm ..hasn't died again since. I also found a poor Harness ground prior to fixing daily constant engine dieing issue.
Last edited by defaultexistence; Mar 6, 2013 at 08:39 PM.