2006 grand prix rpms go up and down at 70mph please help

[dustyn]

i have a 2006 grand prix base only 81,000 miles i just bought it i noticed at about 70 mph the rpms surge from about 2k to 2500 i havent noticed this at any other speeds any help on what this could be would be great thanks in advance dustyn

[Scottydoggs]

your check engine light on by any chance?

and is this at light throttle? just cruisin down the road?

[bsharpminor]

Is the engine warm, are you going up a slight incline?

[dustyn]

no engine lights on it does it when engine is cold or warm doesnt seem to matter and on the interstate no incline a buddy says it is prob the lock up solenoid in trans just looking for you guys opinion

[Scottydoggs]

chances are its the tcc and or pcs solenoids in the trans.

it would be best to go to a trans shop and have it scanned.

[dustyn]

well transshop just replaced the lock up solenoid and pressure switches and it didn't fix it so they say it has to be the torque convertor they called and said it was done I drove it before I paid and the car is still doing it WHAT CAN IT BE???? HELP