Icm keeps going bad

glowstang93

Dirt-Old 20+Year Member
Feb 9, 2003
846
6
39
Illinois
I have replaced the icm twice and it has gone out after about 2 weeks. Am I just getting bad ones or is there something that could be toasting them. I used dielectric grease when mounting.

Thanks in advance.
 
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ICM, what the heck is that?

Year, make, model.

If you are referring to the TFI module, they are prone to failure because they are located where there is excessive heat. Once they overheat, they quit working. There are relocation kits sold on eBay and other online vendors that allow the module to be relocated.

If you are dealing with a later model vehicle with a DIS or EDIS module, stop using generic parts store brands and use a real MOTORCRAFT part.
 
That's weird! I replaced mine back in 2005 (not sure on mileage) and again in May (135k). Where did you buy from?
Oreilly auto parts. It is a Borg Warner. I never had a problem with this brand until now. I'm planning on changing plugs, wires, and icm in the morning. It's a very good possibility that the part is just bad. Changing plugs/ wires just in case there is some arcing or short somewhere.
 
I found a broke plug on the exhaust side, #2. It's really wired since its the easiest to get to and I don't think I broke it while removing it. It was broke clean through right where the ceramic part starts all the way through the center copper. I won't know for sure if that was messing up the icm or not but it sure didn't help anything. She is running fine now at least.
 
104,500 right now. My 18 yr old has been driving it daily but I drove it today. Nothing like fishtail ing on ice covered roads, lol. Now in looking for some plug wire separators. The ones that attach to the valve cover snapped in the cold when I opened them. I may be able to find some local. If not ill wait till summer and visit a junkyard.
 
You don't use dielectric grease on ignition modules. Yes i know they all ship with the crap and i hear even GM service manuals call for it. For proper heat transfer you want thermal compound. I prefer Arctic Silver #5. If you don't believe me do some light googling on this. dielectric grease wasn't designed to transfer heat.

Chris
 
Khan, well, never mind.:nonono:

Anyway, your ICM can fry very easily if you have a leaky coil pack, or a shorted pack. When I had my '91 and I was having the half RPM reading on the tach with the slight misfire, I did my research and concluded that it was the ICM. Replaced it with a generic auto parts store brand, and it worked great for about 6 months. It started screwing up again, and one night while it was dark out I was able to see arcing out of the side of one of my coil packs, that was causing the new ICM to go bad. My advice, replace both packs, wires, plugs, and the ICM. I wouldn't go with the motorcraft one, just because of price, as they all generally go bad if any other issues are going on with the ignition system. Hope this helps and good luck!:nice:
 
Don't disregard my statements. The TFI module was well known for faulure due to excessive heat because Ford choose to locate them right on the distributor. This location gets hotter than the module can tolerate, causing premature failure. This is why towards the final years of the TFI equipped vehicles, Ford relocated the TFI module to either the radiator support or the fender, depending on the model.

For those that question this, after many years of investigation, which was difficult because Ford representatives were quite effective at concealing the problem. But in the end, a class action lawsuit was filed.

A faulty coil could stress a weakened TFI module, but this only account for a small fraction of the TFI failures. Most of the failures are heat related. The remote located TFI modules, like those found on 90's era Ford Aerostars, rarely ever fail. Some companies actually make a relocation kit, which moves the TFI module to a better location, solving the problem on the affected vehicles.

I would definitely go with a Motorcraft one, the quality is so substantially better. Even with the design defects, I have seen stock Motorcraft TFI modules last 10-12 years or more without a failure. Compare to the low bidder made in Mexico or made in China junk you get at the parts store, where sometimes new out of the box parts are of worse condition than the old worn out part you are replacing. Many problems can be solved by using good quality parts. There are some aftermarket parts that are pretty good, but you aren't going to find the good stuff at Advance, Oreillys, or Autozone. For what its worth, my '87 T-bird still has the original Motorcraft TFI module on it. I would take a part that has lasted over 170,000 miles under harsh conditions over one that lasts a couple weeks any day.

Glad you found the issue was a broken plug. A broken plug is on the high side of the coil, should have no effect on the TFI module. Only shorts or excessive resistance on the low voltage side of the coil would cause the TFI module to fail.

Borg Warner used to be a good brand. If you check the part now, it is a part made by a company overseas, and it is not made by Borg Warner.

The only brands I would use are Motorcraft, or Standard.

If your TFI module was failing, you engine will simply stall, the engine will die and will not restart until the module cools down, if that. If you are getting misfires or weak spark, the problem is coming from elsewhere.
 
1991-1993 2.3L Mustangs don't have a TFI or a distributor. DIS, as the OP's car has, given that it is a 1993. I never said to disregard your comments, I just shook my head at you because you were talking about an earlier ignition system.
 
1991-1993 2.3L Mustangs don't have a TFI or a distributor. DIS, as the OP's car has, given that it is a 1993. I never said to disregard your comments, I just shook my head at you because you were talking about an earlier ignition system.
Ok, I see that in the sig. I don't remember the sig being there when I first posted that. Its kind of a hard color to see.

No worries, I don't see DIS fail very often, but these cars are getting old. I still stand by sticking with Motorcraft parts for the ignition system, most OEM parts are much better than aftermarket, unless you can find an aftermarket manufacturer that either makes the OEM part, or specifically makes a better than OEM part.