Lurch and uncle Fester

96 Pont Gran Prix - Lurching Hello. I really know nothing about cars, so I hope someone will be able to help me. I have a 96 Grand Prix, and it runs fine until I get up to around
50 mph, when it starts sputtering and lurching. it continues to do it, and I get frustrated, and press down on the gas more, and when I do this, it runs great again, until I slow back down, and try to stay at 50--which is the main speed around here in nowhere land. Any suggestions on what I should be looking to fix? Other than that problem the car starts quickly, and runs very smooth.
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Do you get any check engine light? Have you checked for codes? If everybody there drives 50 m.p.h., perhaps there's a dead spot on the throttle position sensor at that pedal position.
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i was about to say the same thing (the throttle position sensor) -- but i've had bad throttle position sensors not ever trigger a check engine light, so don't think that light has to be on for that sensor to be bad. you can check (or have a friend that knows how to work on electrical) the TPS with an voltmeter by finding the data wire (there are 3, one 5v+, one ground, & the third is data..... it's voltage changes from near zero, to 5v+ depending on how far the throttle is open) and with the key on in run (but the engine not started) monitor the voltage on that wire, as you slowly move the throttle completely thru it's motions several times. if at any point the voltage suddenly drops or swings high wildly, then recovers, move the throttle back the opposite direction and try to make it do it again. if you are able to get it to suddenly spike, then the position sensor is shot & needs replacing (usually about $20 to $30 at places like autozone, and it is just barely harder to change than a light bulb. simply unplug the electrical connector, remove the two screws, take the sensor off, put new sensor on, reinstall the two screws, plug the plug into the new sensor, you're done - takes a total of 5 minutes to do, and that's assuming you're having to learn english in order to read this first!)
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