So I was replacing the knock sensor and Pigtail on my 1990 with a 3.0(big surprise I know). After taking the plenum off I found the harness is a hacked up mess. Looks like the PO didn't know where to route the pigtail so he put it at the back of the intake, hacked the wires up and ran the connector to the back of the intake to meet it. This is just one of the many wires that has been modified with wire twisting and electrical tape. I'm going to pronounce this harness DOA and start over. My question is does any 89-95 3.0 harness work or do I need a specific year for my 90? Just would like to make sure I get the right one. Thanks!

1990 4Runner 4x4 Auto

 

You need the one for your vehicle year if you want a direct plug and play.

Not sure if you can get a new one yet from the dealer I know the ones for a 87 22re are obsolete

Making another harness work would be just like a engine swap sitting down with the schematics of both year harnesses going wire by wire .

Might be quite a bit of re pinning connectors or only a few .

You might be able to find one coming off a 3.0 being replaced by a 3.4

 

I picked up a 1993 parts 4runner and a 1991 that needs work. What I found was the 1990 and 1991 are compatible. 1993+ is different, knock sensor connector and distributor connector are obvious differences. So finding a plug and play harness as stated would be difficult.