Ok here's an embarrassing update. It's an aftermarket unit. The little metal tab that sits on the outside of the throttle linkage was underneath it. As the throttle opened the TPS stayed stationary not allowing it to do its job. Ugh. What a headache. The tab is supposed to travel with the...
Truck is a 1990 GMC suburban v1500. 5.7 244k. It's an auction vehicle and I'm having a hard time getting it to run properly. It drives fine under very light throttle pressure but big down under harder throttle. It does not drive over 50mph, just constantly down shifts and loses power.
Hooked up...