Hi all,
I have a question that has stumped my machanic.My 2003 Montana when excelarating chugs and than it feels like the tranny kicks in and it runs fine . He's had the scope on it and has checked the tranny and computer and all comes out fine. We dicided to change the computer on it to see if it was a miss reading but that didn't work, so he tells me he is out of ideas. Can anyone give me an idea what it might be ? I'm tired of trial and error game cause it is costing some money so if anyone has an answer please share .

Thanks Pete:confused:

In this order, check: spark plugs (ACDelco only), coil, spark plug wires, Ignition Control Module (ICM), air filter, fuel filter, MAF Sensor, oxygen sensor, and Crankshaft Position (CKP) Sensor. Plugs and coil may be breaking down under load. Misfires can even be caused by something as subtle as corrosion on ECM connections. Most likely, the problem will be with one of the first four items. AutoZone may be able to check the coil and ICM for you for free.

Hi all,
I have a question that has stumped my machanic.My 2003 Montana when excelarating chugs and than it feels like the tranny kicks in and it runs fine . He's had the scope on it and has checked the tranny and computer and all comes out fine. We dicided to change the computer on it to see if it was a miss reading but that didn't work, so he tells me he is out of ideas. Can anyone give me an idea what it might be ? I'm tired of trial and error game cause it is costing some money so if anyone has an answer please share .

thanks Pete:confused:
Have you checked with your dealer for possible programming updates?
Some may be covered by emissions warranties, which run longer than standard vehicle warranties. Have you any DTC's? MIL?