V8 swap, harness questions

There is a certain year cutoff for different engine harnesses.. I can't remember what that year is, but at some point I believe the fuel pump relay was relocated to/from the engine compartment, thus warranting a different harness. Perhaps someone else here knows more about that?

get a harness from a 90 or a 91,they're the same

stangzroastrice said:

get a harness from a 90 or a 91,they're the same

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Can't use a 90 harness, they are a solo year. They look like an 87-89 harnesses but with the air bag plug. And they can't be used for a mass air swap without some modifications.(wiring)

Look behind the driversie strut tower where the engine harnees and the dash harness connect. On the 91 there should be only one plug,, redish looking. On the 90's there are 2, blk & gry. The 87-89's have the blk & gry aslo, but don't have the air bag plug(white plug) on the passenger side. You might be able to use a 92-93 harness, but not sure I have never tried 92-93 harness in a 91 car. Call MPS racing in Atlanta, they can tell if a 92-93 harness will work.

you can run an 91 or early 92 harness without issues. You cannot run a late 92/93 harness because they relocated the fuel pump relay to under hood.

The breakdown reads -
87-89 fine
90 solo
91 early 92
late 92/93

I have a 93 coupe I did a conversion on, tried to use an 89 harness, didn't work. I tested it in a 90 car, it DID work, but we only tested it, didn't drive it around.
Save the time and hassle, get correct year harness and EEC.

In other words to be safe just get a 91 harness!