Ok, I replaced my ecm and after a few days it started fine, Now it's sitting in a 7 eleven parking lot. I need a wiring harness asap
and I need to know which years can be used as an acceptible donor car. 88-92 correct. I've been calling every yard in L.A. and been finding nothing.

thanx in advance

 

'88-'89 are maf systems. '91-'92 are speed density. I think the '90 is also speed density, but am not sure. One problem with speed density is that maf cars had a separate harness for the engine/ecm. When G.M. went over to speed density, they put all of the vehicle's wiring in one harness. If your car is speed density, you'll need to completely rewire the car to replace the engine harness. If your harness hasn't been "butchered" you shouldn't need a new harness. You just need to clean up all of the connections at every sensor, relay, the ecm, and any other components that are plugged into the engine harness. Even if there are some badly done connections in your wiring, you can fix them by making solder connections and then using heat shrink tubing to seal them up.

 

He's got an L03 TBI, they're all speed density. The only difference is 88 and 89-92. The later years have VATS and use a different computer than the 88.