What does the Ignition Control Module do?
 

I have a 1992 F250 with a 5.0 & E4OD transmission. I've been having issues with starting it and I think it's the ICM. The ICM is the fender mount style, gray in color and the number on it is E7DF-12A297-A1A. My question is, what exactly does the ICM do? Are there anyways to test it? I've seen people post that they had them tested and they passed but were still bad. My truck has a very hard time starting only when it's cold out. It was 55 Fahrenheit outside the other day and it started decent. any temp above 65 it'll start great! When it's cold out it runs like crap until it warms up. It acts like it's on 2 cylinders. But once it warms up it's great! I've changed lots such as ECT, O2, IAC, plugs, wires, cap, rotor, coil, exhaust, air filter, TPS, EGR system, and the fuel system tested fine and the parts are new anyway including the filter. It acts like the coil is cutting out and the timing doesn't wanna sit still much. The idle changes randomly and I believe it's because of the timing moving around. I even believe I hear labor knocks / pings as is the timing is too high. I already advanced it and now turned it back down to 10* and still hear sometimes. Is this what the ICM does? I would really like to know EXACTLY what the ICM does just for reference reasons. Thanks In Advance!!


** Forgot to say that I checked for codes and KOEO I get 111 and sometime 625, and then continuous 512, KOER I get 111.

You may have the wrong ICM installed. It should be black in color. Take a look at post#9 in this thread: https://www.ford-trucks.com/forums/1...-stranded.html

Some good reading here on ICMs: http://www.msextra.com/doc/ms1extra/...n-tfi-edit.doc

I actually believe it's the original one. I've had it in there for the 4 years I've owned it. It was on the truck wneh I bought it. I never had these issues before. But thanks for that info! I'll check it out.

The last link didn't work:'(

Ford ICM are very corrosion sensitive. Maybe you have a bad connection, or a crack in a connector affecting contact.

You could have a bad engine coolant sensor by the thermostat being that its temp related.

Coolant sensors are new. I'm wondering if it's a dirty connection at the PCM. I just didn't know if the ICM is what controls the spark and timing. It seems like the coil cuts off. Strange thing is if I take off the starter relay wire and hold it in start it runs great! So I don't know haha

I did a little more research, I do stand corrected. The correct ICM would be the gray Push-start version. The Black CCD version is for 1994+ trucks.

I apologize for leading astray on the subject.

Try this: Index of /doc/ms1extra/MS_Extra_Hardware_Manual_files

Then scroll down and select "ford-Ignition-tfi-edit.doc"

I had exact same problem on my 1994 Ford F150 Ford XLT with 5.0 engin Orielly's Auto Parts will check the I.C.M. for free but I bet it is the Pick Up Coil in the Distrobetrer.

I had exact same problem on my 1994 Ford F150 Ford XLT with 5.0 engin Orielly's Auto Parts will check the I.C.M. for free but I bet it is the Pick Up Coil in the Dist.

Yes the ICM controls spark timing by switching the Coil output off and on..

What do you mean by " hold it in start it runs great!" ?
Define "it" ?

The starter relay wire is also the Start position power to the TFI Ignition Module, ICM. There is a potential for the starter relay wire to bleed the ICM to ground after the engine is started and the Ignition Switch returns to the on position from Start. Removing the starter relay wire removes the ground path.

Man, there was a guy out here last week with a similar issue, I don't remember seeing a resolution....