Pontiac Repair: savana van pt 2, throttle position sensor, timely reply

Question
thank you for for your timely reply. the problem goes away about 1 to 2 per cent of the time when driving, yes the engine check light is on, i have tried disconecting the maf(i think) just after the air cleaner and no change, cleaned it as well, same outcome. how hard is the throttle position sensor to change? any special steps to take or just take off and put on.  again thanks for your help.  you've given some answers that are different from the status quo.

Answer
well the TP depends on wether this is a drive by waire engine or it has a throttle cable. if it has a trhrottle cable it is just a plug a play part if it's drive by wire it's part of the whole throttle body and it's VERY VERY expensive and again I sid it was a guess I hate to see you throw another part at it as a guess. I would have the van scanned for codes at one of the big box parts stores and see what is stored and that will give you something to start with to look at.