The ICM is the grey long plastic piece attached to your distributor. This is where the plug is attached for controlling spark.
3.8 liter motor's ICM is remote mounted - on the firewall to avoid the heat issue.AnswerLook at the distributor. There will be a module on the side that is either grey or black, and is about 3 inches long and 1 inch wide. It is held onto the distributor with two 7/32(5.5 mm) screws back inside of two holes on the module. You will have to get a thin wall socket to access them. I use a 1/4 drive deep well Sears Craftsman socket to get them off. NOTE: 7/32nds inch and 5.5MM are the same size, so either will work. 3.0 ICM Overheats(from the "Related Question" below)
The 3.0 liter Taurus - Sable engines has a known ICM problem - Ignition Control Module - even a recall was out for this issue - ICM mounts to Distributor base, runs hotter than the motor - the ICM dies early.
My issue was stalling after 2 hours freeway driving - would stall after pulling out for break or gas - OBD codes were 111 (KOEO) and after engine restarts (post cool down of 15-20 minutes, hood open) was also 111 (KOER). These are 'nothings wrong' codes. I did notice that there was NO spark when stalled, but fuel pressure was there and injectors clicked while cranking (stethoscope).
I added a 2" * 28" 'preheat duct' tube from behind left head light to an inch or so behind the ICM/distributor base. I haven't stalled since I did this. Tube cost, Napa Auto, was less than $10.00. If anyone else tries this and they might be in a traffic congested area, might want to add a 12VDC PC CPU cooling fan - about another $10-12.Answer
The control module is either fenderwell mounted or it is mounted on the distributor body. Try this ; go to a auto parts store and price one out and look at the part; then you will know what yours looks like. The one on the distributor will require a special wrench.
update... the ignition control module on a 1992 mercury sable is located on the distributor. it requires a special 5.5mm ignition module removal tool that you can find online. and don't forget the hi temp grease!!
Ahhh... The bolts troubled me for quite some time. As with all of our lovely American cars, they love to make ***special*** tools to remove what should be an easy part to remove. Instead of just attaching the module with simple Phillips screws, the engineers at ford decided to affix it with a 5.5mm bolt. ***however*** since the bolt is recessed about 1/2 inch, there are **no** deep well sockets that will reach it. So... You have to buy a ford "ignition module" tool to access those pesky bolts. I found one online for about 10 bucks. Also, don't buy the module from ford! They want over $215 dollars for it. I got one at checker for about $105.00.
Steve phx AZ
The 1990 Chevy Celebrity engine is distributorless, the ignition is handled by a combination of the engine control module(computer) and the ignition control module. You did not mention which engine the car has. If your car has the 4 cylinder engine the ignition control module is below the intake manifold at the rear of the engine. You can follow the spark plug wires to it. The coils are mounted to the ignition control module. If your car has the V6 the ignition control module is near the starter and again you can follow the spark plug wires to it. Again the coils are mounted to the ignition control module.
The ignition control module is located directly beneath the coil packs. These can be found at the rear of the engine, on the top center. Just look for where all the spark plug wires connect, those are the coil packs, and they are bolted to the ignition control module. It has three electrical connectors, two on the driver's side and one on the passenger's side.