My 87 Grand National was running a little rough and popped during boost. I put a new coil and module. Double checked all the wiring. It runs worse than before, backfires and stalls at idle. Help!
I have seen a T type have all sorts of problems due to a simple battery connection. Your'e going to have to also check vacuum lines, the turbo it self, poss. compression. "during boost" how much psi? stock turbos vs aftermarket are a lot more forgiving, but depending on upgrades, def. sensors, you might have a long road in front of you.
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