Does anybody have a photo or photos on how the wiring harness wraps around the engine. I put in a different 3.1 engine in my 1990 firebird and think I got it to fit, but the plastic shield around the wires melted by the exhaust.

Also the car idles fine when it is cold but when warmed up it starts to misfire and I notice sparks from the metal heat shield shelves around the spark plug wires. I don't think that it is the spark plug wires because I replace the set twice. Also at night i can see corona discharge throughout my wires without the metal shelves on.

I replaced the spark plug wires, cap and rotor, fuel rail, o2 sensor, map sensor, plugs are new, clean, and are gapped right.

 

Need some less cheap plug wires there, and to make sure they get all the way down on the plugs.

Unfortunately, I don't have a pic of the FSM wire routing diagrams, but I can tell you I did the same thing and it's a real trick to getting the harness routed the way it needs to be to reach everything AND be far enough away from the exhaust manifold and pipe. I'm assuming this is just over the starter, right?

 

I think I might have figured it out the wiring harness was shorting out on the exhaust causing the metal sleeves to spark.

I redid the wiring harness and it seems to be running better with no arc coming from the sleeves.

Thank for the reply though.