I've got a 94 Xtra Cab Pickup I've been doing a bit of work to. It came with the 2.4L 4-cyl and I've swapped in a 4.3L Ecotec engine. I have the 4.3 running with it's own harness and am looking to delete as much of the old harness as possible. Problem is, I can't get power to my air conditioning unit or water temperature sender via the old harness. It seems as though it was supposed to pick up power somewhere in the old harness that's no longer active, and I haven't had any luck finding where that may be. I was wondering if anyone has had this issue with any other swap and what was done to solve it. Thanks

 

Every swap is different you need the Wiring diagrams for your 94 pick up

The one of your engine harness .

Then sit down and make them play nice together .

Or you could go trial and error with lots of frustration and time and perhaps fires !!