94 ICM Problems
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Teching In
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From: Mason
94 ICM Problems Ok so I just got from up north today it was about a 2.5 hour drive and as soon as i got home (as i was pulling into the driveway) the engine stalled without warning. it did the exact same thing when i pulled into my camp site on the way up. (i feel very very lucky haha) I did some reasearch and alot of people on the forum even has the exact same problems and symptoms with thier cars replaced the ICM and was good to go. So about 2 hours ago I bought a replacement icm and installed it. the car started up ran good for about 10 minutes then started spittering and sputtering mis fireing like a mad man then died. oddley enough i went tightened the icm ( i was curious if i had not tightned it enough the first time) the car would turn over but not fire. 5 minutes later the car started right up and ran great for another 10 minutes then died again. I tightened it a second time now the car runs and wont stall but runs super weak, it doesnt have the power it used to and you can hear it slightly miss firing if u give it a lil gas 1500-2000rpms ect. PLEASE HELP! I am so confused as to what is going on!!!!
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Teching In
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From: Mason
I replaced the opti plugs and wires 2 summers ago (about 18K ago), and fuel pump last summer (about 7k ago) do you think it could have gone bad already? also the car seems to be running a lot better since i re tightened the ICM for the final time. I'm thinking maybe bad icm ground?.. Is that possible?
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Joined: Dec 2008
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From: Little Rock, AR
Well, you are doing replacement without any diagnosis. It may be so, but you didn't even confirm the trouble was spark related. Plus any part of the ignition system electronics (opti, ICM, coil) or their connections can fail when hot and work when cooled down. But so can the fuel pump. So, a little diagnosis may be a good thing to do.
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Teching In
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From: Mason
I checked the fuel P when the car was cold it was right where it should be, I have not however checked when its hot. I replaced the coil today just for the hell of it the car has been running good all week. However when i got home today it stalled again right when my subs hit (weird). This time when i went to check the icm bolts one of them seems to be stripped so Im really starting to wonder if a bad icm ground is the issue. I really hope its not the opti lol. But thanks for the help guys
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Look at the coil....they are cheap (around $20) Don't know how or why it happened, but the last time my ICM failed it took out my MSD coil too. 
Both had to be replaced and it was good as new 
If it does turn out to be the opti, your only out $20 and have an extra coil laying around. Or, take the extra time to properly diagnose like shbox mentioned.
Both had to be replaced and it was good as new If it does turn out to be the opti, your only out $20 and have an extra coil laying around. Or, take the extra time to properly diagnose like shbox mentioned.
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Verdad Gallardo Thread Starter
Teching In
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From: Mason
it was the opti, I had an oil leak on the front of my intake and it drained into the opti cap and ruined the unit. I also replaced to coil and coil wire and that seemed to help to. Car runs good now. However I believe my icm wire is still bad because if i wiggle the icm conector while the car is running it will stall.
