I have a 96 z28 and also have a second lt1 from a 94(eng.,harness,pcm), can I use the coil (msd) and icm off the 94 with just swapping out the harness wiring at the coil and icm to the 96?

 

I thin k that the ICM's are the same but not 100%
so from what I gather
on the dual connector:
ON BLACK CONNECTOR
pink-12v through 10 amp fuse from ignition
ON GRAY CONNECTOR
pink/black-to terminal "A" on ICM
white/black- to terminal "D"on ICM

ICM PINOUT on both models:
C-A-D-B

so should I just try to trace the pinout that they go to and switch harness if the ICM are the same,
if not I have heard that the white or wht/blk wire off the gray connector on the coil is the tach wire which is 4 PPR.
But, I cannot find the 96 wiring, can I just check for 12v off my 96 to go to the pink 2 connector harness, then try and crank it with my DVM on hz to see which changes as the car cranks to go to the white wire on the 2connector harness
so then what do I do with the third wire????????.

 

For 96, on ICM connector (4-pin):
A is 12v + switched
B is Ignition Control (to PCM)
C is Ground
D is Primary Coil Driver (to pin B C1 on coil connector)

On Coil:
A C2 is 12v + switched (same wire circuit as A on ICM)
B C1 is to pin D on ICM connector

The 94-95 has a different ICM than the 96-97, they have different part numbers. Also, the 96-97 has a female coil connector, so you will need a different coil wire. Hope this helps.

 

The OBDI ICM is powered by the coil. The OBDII ICM is powered directly from the fuse. But that's handled by the wiring harness. Since the 2 ICMs have different numbers, I believe the connectors are different. I see the 94 ACDelco D1986A has the same style connector as the 96-97 ACDelco D579. However the location of the corresponding pins may not be in the same order. See if they are labeled on the part itself.

One other way you might be able to test this part without actually replacing it would be either. Turn power on but engine off and see if the fuse blows after a certain amount of time. If so, repeat the power on waiting process but this time with the ICM disconnected.

The more scientific way would be to measure the current the ICM is pulling. On the 96-97 vehicle this means pulling out the pink wire going to the ICM and putting your voltmeter (set to 10amp scale) in line with the pink wire and the pin on the ICM. This is not very practical however.

FYI, Advance has the best selection from several different sources of this part including ACDelco.

 

first off sorry I took forever to reply back again, I didn't save this to my favorites on my pc and it was harder for me to find.

on 94 and 96 from what I have found both Icm's have the same functions per terminal but what I am unsure of is their orientation
ICM connector (4-pin):
A is 12v + switched
B is Ignition Control (to PCM)
C is Ground
D is Primary Coil Driver

I know 94 is CADB, I need to go check what 96 is though, I am not 100% but I think that they are the same.

as far as coil wiring itself
On Coil-96':
C1 is to D on ICM-Primary Coil Driver
C2 is to A on ICM-+12v

On Coil 94':
gray connector
A-white/blk to D on ICM-Primary Coil Driver
B-pink/blk to A on ICM (+12v)-powered through the coil since Both B's are joined together inside of the coil
black connector
A-Not used
B-pink wire is +12v from fuse

so correct me if I am wrong, but if all seems correct I think I will give this a try this weekend