2006 Pontiac Grand Prix M Driving On Interstate Set Cruse Control 73 Mile Per

2006 PONTIAC GRAND PRIX
11,100 MILES
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ANONYMOUS
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When I'm driving on the interstate, I set my cruse control at 73 mile per hour. As I'm driving my tech will rev up then drop back this goes on ad on. It will run at about 23,hundred then jup up to 27 hundred for a few secs then drop back for a few min then ack up. Any Idieas what this can be. Thanks
Apr 10, 2013 at 12:32 AM
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CARADIODOC
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That is typical of the transmission's torque converter unlocking and re-locking for better fuel mileage. It is supposed to unlock when the throttle is almost fully released, as in preparation for coming to a stop, and at wide-open throttle. Most commonly it will unlock when the cruise control fully relaxes its throttle cable when going downhill and the car is picking up speed. Once the car is on level ground or going uphill, the torque converter will lock up again when the cruise control pulls on the throttle. If the unlocking occurs randomly on level roads, suspect a problem with the throttle position sensor.
Apr 10, 2013 at 1:03 AM
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STEVENELLIOTT1
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Thanks for the advice
Apr 10, 2013 at 1:14 AM
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