Pontiac Repair: 97 bonneville, mass air flow sensor, mass air flow

Question
I have a 97 bonneville that at about 2200rpms it lugs it is very sparatic and It has done it ever since i bought it with 60000 on it. I have had a new moter a new tranny fuel filter and fuel pump the mechanics can never seem to catch it.  it is a v-6 with 126,000 on it.  anyb help would be appretiated thanks.

Answer
Hi James:

Well it can be a lot of different things. It would look at the mass air flow sensor or a map sensor as being the problem. you can un plug either of them and take the car for a ride and see if it runs any better with either of them unplugged. with them un plugged the car will have a hesitation from a stop but after that see if it "lugs" still at 2k RPM's. If still no change I would take at the fuel pressure. if it's low it could cause this. Another thing to try when the car is "lugging" at that 2K rpm's keep you foot steady on the gas and just tap the brake pedal and see if the lugging stops. you could have an issue with the transmission Troque Converter Clutch. or when the TCC is applied the slight engine miss you feel is felt worse when the TCC is applied. You could have dirty injectors and you have a slight lean misfire going on and again when the TCC is applied you feel it more... Good luck :)