Pontiac Repair: rpm surge, mass air flow sensor, mass air flow

Question
We have a 2006 grand prix, 3.8 liter v6, 80,000 miles. While driving 40 or over the rpm's surge from 2 to around 2.5. Car runs great doesn't have problems shifting at all and no noises. Took it to a dealer and they have no clue. They have put in a new trans pump but since that didn't fix it they wanted to rebuild the whole trans. We don't have that kind of money and don't think that this really needs done or is the problem.

Answer
Hi angie:

I'm really not a trasnmission guy but I'll try to help you out here. you have no other issues with up and or down shifts? has the service engine soon lamp come on? when it's hot does it shit hard? when it does this say at 45 MPH and you feel it acatually shift into 4'th gear try this hold you foot steady on the gas and with your left foot put light pressure on the brak pedal and see in the RPM fluctuation goes away. It could be an issue with the Torque converter cluth. when you apply the brake pedal it cuts out the TCC and keeps it from applying. one other then to try is this unplug the MASS air flow sensor and drive the car. the service engine soon lamp will come on and the car will hesitate from a stop drive it normally and see if that surge goes away. if it does it could be just a dirty MAF. good luck :)