Help relocating ICM in 89 corsica
-
- Registered User
- Posts: 1
- Joined: Fri Jan 31, 2025 3:23 pm
Help relocating ICM in 89 corsica
I've got a 1989 Corsica 2.8L, and I'm having troubles with corrosion with my ICM and wondering if it's possible for me to relocate it.
I spoke to a mechanic about this and he said if I can get the plugs to the ICM (not the icm to coils) he could make it work. But I've noticed not only does the ICM have the average plug connectors, but it has 3 plug ins at the bottom, and I'm also wondering what do those plug into?
Thank you!
I spoke to a mechanic about this and he said if I can get the plugs to the ICM (not the icm to coils) he could make it work. But I've noticed not only does the ICM have the average plug connectors, but it has 3 plug ins at the bottom, and I'm also wondering what do those plug into?
Thank you!
Re: Help relocating ICM in 89 corsica
I relocated my ICM on both my '90 3.1 Beretta and my '95 3100 Z-26 when I swapped-in the 3.4 DOHC LQ1 V-6, both of which use the same ICM as your Corsy.
The three wire connectors to the ICM are:
-Power/ground (two-wire, pink/black or pink, and black or black/white),
-7x Crank Position Sensor (CKP -a two or three-wire connector with a purple and a yellow twisted pair and possibly a RF reducer 'ground' wire that goes nowhere but contacts a tinfoil 'shield' wrapped around part of the harness. The sensor is located in the rear of the engine-block on the V-6s, and it is very important to keep those wires twisted around each other like they are),
-ECM signal/feedback wires -this is the big plug and sends engine RPM data to the ECM, and receives commands from the ECM for spark-timing modifications.
A good place to relocate the ICM is behind the right strut-tower. You will need different plug-wires (aka 'Ignition Cables') as at least a few of them will otherwise be too short. You might be able to do it with a set for a '95-96 3100 Beretta/Corsica, but not certain on that. I liked the yellow Accel brand performance wires, cut-to-fit style for the V-8s and just used what I needed, they were always good cables and cheap too.
The pink or pink/black power-supply wire should be able to be pulled out of the wire-loom enough to get it to reach to the new location if you go behind the strut-tower, but the ground-wire will not reach. Either cut and splice with a good solder and heat-shrink tubing, or just crimp an eyelet on the end of the ground-wire and ground it out somewhere with a self-tapping screw -just make SURE you get a solid ground or you will get stranded somewhere someday.
Both the other wiring connectors should reach without a lot of trouble or drama.
Of note, make sure your new spark-plug wires run clear of the serpentine belt and the power-steering pump, and are physically pinned, clipped or tied in place. They will get worn through very quickly and cause a misfire otherwise -I had this happen on the '95 Z-26 Quad-Cam LQ1 car I Built when the wires slipped out from the cover I was running them under. It is a different engine, but the blocks are virtually the same and the belt accessories are mostly the same too (aside from the A/C compressor location) and the P/S pump is where one of my wires got abraded. Even if the wires look good to go, remember that the engine will shift and rock a little in the bay constantly while driving through traffic, and can easily coax a wire into the wrong area.
Keep us updated, I'm curious to hear what you end up doing with this...
The three wire connectors to the ICM are:
-Power/ground (two-wire, pink/black or pink, and black or black/white),
-7x Crank Position Sensor (CKP -a two or three-wire connector with a purple and a yellow twisted pair and possibly a RF reducer 'ground' wire that goes nowhere but contacts a tinfoil 'shield' wrapped around part of the harness. The sensor is located in the rear of the engine-block on the V-6s, and it is very important to keep those wires twisted around each other like they are),
-ECM signal/feedback wires -this is the big plug and sends engine RPM data to the ECM, and receives commands from the ECM for spark-timing modifications.
A good place to relocate the ICM is behind the right strut-tower. You will need different plug-wires (aka 'Ignition Cables') as at least a few of them will otherwise be too short. You might be able to do it with a set for a '95-96 3100 Beretta/Corsica, but not certain on that. I liked the yellow Accel brand performance wires, cut-to-fit style for the V-8s and just used what I needed, they were always good cables and cheap too.
The pink or pink/black power-supply wire should be able to be pulled out of the wire-loom enough to get it to reach to the new location if you go behind the strut-tower, but the ground-wire will not reach. Either cut and splice with a good solder and heat-shrink tubing, or just crimp an eyelet on the end of the ground-wire and ground it out somewhere with a self-tapping screw -just make SURE you get a solid ground or you will get stranded somewhere someday.
Both the other wiring connectors should reach without a lot of trouble or drama.
Of note, make sure your new spark-plug wires run clear of the serpentine belt and the power-steering pump, and are physically pinned, clipped or tied in place. They will get worn through very quickly and cause a misfire otherwise -I had this happen on the '95 Z-26 Quad-Cam LQ1 car I Built when the wires slipped out from the cover I was running them under. It is a different engine, but the blocks are virtually the same and the belt accessories are mostly the same too (aside from the A/C compressor location) and the P/S pump is where one of my wires got abraded. Even if the wires look good to go, remember that the engine will shift and rock a little in the bay constantly while driving through traffic, and can easily coax a wire into the wrong area.
Keep us updated, I'm curious to hear what you end up doing with this...

1989 SuperCharged 3800 Srs-II (First)Six-Speed GTU
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26
1990 Turbo 3.4 5-Speed T-Type
1990 4.0L 4-Cam 32-Valve V-8 5-Speed Indy GTi (Project)
1990 Stock(!) 3.1 MPFI Auto Indy
1995 LA1/L82 4T60E Z-26
1995 3.4 DOHC Turbo 5-Speed Z-26