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View Full Version : 1990 Civic Keeps Shutting Down... Faulty Ignition Control Module?


civicsufferer
Apr 4, 2014, 07:08 PM
Hi Folks, I'm brand new, so bear with me while I try to explain this. I've got a 1990 Honda Civic DX that has been giving me fits for the last four months. It runs great and then stalls with no predictable pattern. Sometimes it won't start after running fine when I shut it off (usually after sitting in the sun on a warm day), other times it stops as I'm pulling out from a stop sign or while I'm driving down the road at 50mph. No lunging or lurching, it just loses power and coasts to a stop with the red dash lights on (sorry I can't remember if the yellow CEL was on). Usually it will start right up after I stop, or at least after sitting for anywhere from 5 minutes to 2 hours. Then it runs fine for a while until the whole process repeats itself. I see that most of this sounds exactly like the Ignition Control Module problems several other people have been having. And my mechanic replaced the ICM about a month ago. The car ran fine for a couple of weeks and then started doing the same things again. Prior to replacing the ICM. I wasted a couple of months chasing the fuel supply system. I swapped the fuel pump with a new one and then put the old one back in last week to see if there was a difference (there wasn't). Before that, I also gathered a host of spare parts from the scrap yard and swapped out the main fuel relay, both injectors, the fuel filter (that one was new), a couple of vacuum pumps and just about every fuel-related sensor I could find under the hood. Nothing made any difference until my mechanic finally replaced the ICM. I can hear the fuel pump running when I try to restart the car after it stalls, so I'm pretty certain it's an ignition problem. I see that many of you recommend silicone heat transfer compound on the ICM, I'll check with my mechanic to see if he did that. He's got over 50 years of experience, so I'm guessing he did. Also, the ICM was over $100.00 so it was probably a good quality replacement. He may be able to swap it out under warranty. I don't think he replaced the distributor cap, rotor or coil. It sounds like that might be a good idea. The problem is that I'm on a limited budget and this is my commuter car for work (about 80 miles a day). I've tried to keep the cost down, but I need this darn thing to run reliably. I could really use some advice on exactly where to direct my time and money. At this point I'm just about ready to put a bullet in the block and walk away. civicsufferer Nampa, Idaho

TxGreaseMonkey
Apr 4, 2014, 07:32 PM
Yes, make sure your mechanic applied a thin, even coat of silicone heat transfer compound to the back of the new ICM--otherwise, it won't last long. After that, I would install a new ignition coil. I recommend doing this every 125,000 miles or 10 years, whichever comes first. High resistance in the rotor, distributor cap or wires often can cause ICMs and coils to fail. These items should be replaced every 60,000 miles. If the problem persists, I would install a NEW main relay--cold solder joints on the printed circuit board could be expanding and losing current, when the ambient temperature goes up during the day. Should the problem continue, install your new ICM and coil in a genuine Honda distributor housing--all others are suspect and unreliable.

civicsufferer
Apr 5, 2014, 09:20 AM
Yes, make sure your mechanic applied a thin, even coat of silicone heat transfer compound to the back of the new ICM--otherwise, it won't last long...

Thanks TGM,

I've seen that you regularly respond to these civic inquiries and I want you to know that your assistance is greatly appreciated by those of us struggling to figure out Honda's maze of quirky sensors and control systems. I forgot to mention that my mechanic also replaced the valve cover gasket a couple of weeks ago after we found that all of the spark plug wells were full of oil (up to a couple of inches on top of some of the plugs). I don't know how long the plug wires were exposed to the oil, but I plan to replace the wires along with the cap, rotor and coil. Could you tell me where the main relay is located? I finally found the main fuel relay, but I'm not sure which one is the main relay you're talking about.

TxGreaseMonkey
Apr 5, 2014, 11:05 AM
For a 1990 Civic, the main relay is located just above the fuse box. Turning the ignition key on and off will help you locate the main relay, by allowing you to hear and feel it "click." Main relays often have 7 wires going to them.