2002 Pontiac Grand Prix Shaking when driving at 40mph

2002 PONTIAC GRAND PRIX
120,000 MILES
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ASHLEYBOO904
  • MEMBER
  • 1 POST
The car cranks up and runs good until I get about 40mph or higher, What could the problem be? I was told it maybe the water pump but i'm not sure what is going on with it. It just shakes/vibrates, Please contact me back THANKS!!!!
May 31, 2013 at 11:42 AM
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JDL
  • CAR REPAIR CONTRIBUTOR
  • 16,098 POSTS
How long since a tune-up? If you think it is a fuel issue, check fuel pressure. Check for applicable trouble codes. Some of the national brand autostores will check codes for free. The autostore may loan out a fuel pressure gage. You may have to put up a deposit, but, you get your money back when you return the gage.

I'm not sure of your engine litre size? Most sixes have a schrader valve on the fuel rail, where you connect the fuel gage.
May 31, 2013 at 12:55 PM
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