'96 C1500 4.3/4L60E - Misfire after Trans Swap

[AboveTheLogic]

Oh that makes sense! Thank you.

 

[Schurkey]

That's the important difference between a "lean condition" and a lean sensor signal.

 

[AboveTheLogic]

Replaced the distributor cap and rotor, plugs, and wires.

Fired up, ran smooth at idle. After a few minutes, rough running returned.

I didn't expect that to fix it, but I was hoping. Now I need to really fix it and limit test drives to not foul my new plugs.

I picked up a cheap smoke tester to check for leaks. Fuel injector testing kit coming later in the week.

I think I left out an important point - the left turn signal light is on...sometimes. The left headlight sometimes works. This was a problem before I pulled the trans, before the misfire got this severe. The last 2 test drives, I noticed a burning smell. Just a few minutes ago I noticed one or two of the wires going to the starter were making contact with the passenger side exhaust manifold, so I pushed them down.

Next steps....

-Smoke test for leaks.
-Follow FSM steps to check for electrical shorts at the O2 sensor.
-Injector balance test.
-Locate, inspect, and if necessary, replace ground straps. I don't know where they all are and will look for a diagram. If there is supposed to be one at the starter, that may be my problem.