Having problems with your 2002 Pontiac Grand Prix ?
02 grand prix 3.8 engine will not go above 3500-3600 rpm. if i try to drive it it barely can get out of first gear because that is the shift point. when it does go into second it will only get up to about 45 mph. passing gear will not work.
Two things i can think of, 1) a restricked catylitic converter. 2) faulty fuel pump or injectors. check your fuel pressure a the fuel rail to test the pump. a plugged cat. will cause back pressure in the exhaust, if the car is good and warmed up ( at night or very dark place ) look at the "Y" pipe attached to the exhaust manifold, if it glows a dull cherry red replace the converter.
Repair Help & Product Troubleshooting for 2002 Pontiac Grand Prix
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