hey guys i have a question i have a 1991 f-150 4.9l would like to know which icm i should use black computer controlled or gray push start kinda cofused thanks in advance

 

No reason for a poll. A quick search on this forum will tell you that you need a gray colored push-start style ICM. Ford did not start using the black ICM/CCD style ignition until 1994.

Many part manuals, including Ford are wrong....you need a gray colored Push-Start ICM. No ifs, ands or buts.

 

The black ICM(TFI module) will run with a older ECU but will not work properly as the black TFI does not control the dwell to the coil, it expects the ECU to do that. You will get hard starting ,engine pinging and misfires with the black TFI module.

 

Ok great thanks guys. Now to find the root of my problem