I have a 2002 supercharged pontiac gran prix. When the supercharger kicks in the engine misses and the car runs sluggish. I also hear a hissing sound. Could this be an egr valve problem?
It could also be a plugged catalytic converter. I would have that checked out first.
It could also be bad vacuum lines... I would check this first it a cheap fix and those house could all be very dry and cracked.... I have a 1999 and I have had to change all of mine all ready...
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