90 to 91 P body engine harness difference

[135sohc]

Awhile back I bought (what I was told anyways) was a 90 2.5 T-1 P body underhood harness. Didnt think anything of it until the other day when I got it out to look it over and I noticed a BIG difference in where it plugs into the dash harness. Existing dash harness in the car now uses 2 large (if fully equipped then 3) multi pin connectors. Each one has 16-20 pins iirc.

This turbo harness has several smaller connectors instead of just the 2-3 large ones. Thats a big problem and puts a wrench in my plans. So I was wondering if anyone knows what year P body cars went to the large multi pin connectors ? and if anyone could look and tell me what type of connectors a 91-92 P body turbo harness uses that would be great also.

I've got an extra TBI P body harness now and am thinking about just adding in the extra injector wires, other sensor wires and relocating the TPS & IAS connectors and just dropping it in.

[Captain Chaos]

Awhile back I bought (what I was told anyways) was a 90 2.5 T-1 P body underhood harness. Didnt think anything of it until the other day when I got it out to look it over and I noticed a BIG difference in where it plugs into the dash harness. Existing dash harness in the car now uses 2 large (if fully equipped then 3) multi pin connectors. Each one has 16-20 pins iirc.

This turbo harness has several smaller connectors instead of just the 2-3 large ones. Thats a big problem and puts a wrench in my plans. So I was wondering if anyone knows what year P body cars went to the large multi pin connectors ? and if anyone could look and tell me what type of connectors a 91-92 P body turbo harness uses that would be great also.

I've got an extra TBI P body harness now and am thinking about just adding in the extra injector wires, other sensor wires and relocating the TPS & IAS connectors and just dropping it in.

I ran into this problem when converting my 93 Shadow to a turbo. I had a 90 harness and when I went to plug into the dash harness I found what you found. I then thought I could swap the wires into the 93 connectors, wrong they are different size. I finally found a 91 turbo Shadow at the jy and that engine harness plugged right into my 93 dash harness. There were a couple wires that had to be repinned for headlights and brake lights to work but it plugged right in. HTH.

[135sohc]

Excellent. So a 91-92 harness is the way to go then.

[turbo84voyager]

No, dont buy another harness or mofy a tbi one, you can use a 90 harness in a 91. My 91 shadow has a 90 shadow harness. I did it without any major issues. Just carefully remove the connectors from the 90 and put them in the 91 plugs from your TBI harness one at a time. I believe a few connectors might have been different, in these cases I matched up the wires, soldered, shrinkwrapped and taped. Make sure you solder any new connections, dont trust but connectors or anything like that. You need a FSM or a copy of the wiring diagrams for both years for the engine harness to do this because I believe there are a few different wire colors ( its been a few years since I did the swap).