I have a 2004 grandprix and when i start it it makeing a knocking noise but goes away but it seems like the sound could be coming from one of the tenion pulley
Are they tight? or wobbly?
That's not much information to go on, but if the knock is coming from inside the engine it could mean engine failure is imminent. If you're not able to isolate the source of the sound yourself you need to find a professional who can. Hopefully its something minor like a bad accessory pulley.
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