1997 Pontiac Grand Prix Acceleration

1997 PONTIAC GRAND PRIX
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SQUASH9146
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1997 Pontiac Grand Prix 6 cyl Automatic 160000 miles

I recently bought a used 97 pontiac grand prix with 160,000 miles on it. My problem is with the acceleration. When I start driving it goes to 25mph pretty quick then all of a sudden it accelerates really slow till about 45mph and then picks up pretty normal. So basically only very slow acceleration between 25-45mph. Do you know what the issue might be?? thank you.
Aug 18, 2010 at 5:57 PM
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RASMATAZ
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Do you have a check engine light on and when was the last tune-up?

Lack of acceleration,chugging,hesitating,bogging,misfiring etc. could be caused by one of the following below:

Start here check and test all the items below and comeback with results.

Oxygen sensor.
Catalytic converter.
Fuel injectors dirty/sticking.
Mass airflow sensor/Airflow meter.
Throttle position sensor.
Crankshaft position sensor
Knock sensor
Manifold absolute pressure sensor.
EGR Valve
Fuel pressure regulator leaking or defective fuel pump.
False air leakage.
Fuel contamination.
Foul/defective spark plugs.
Open spark plug wires.
Ignition coil/Coil packs defective.
Incorrect ignition timing.
Cap and rotor.

Note:If it doesn't apply disregard it.
Aug 18, 2010 at 9:00 PM
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