Poor performance - Dealer can't fix
 

I have a 2001 V6. It has been to the dealer 3 times for the same problem. It hesitates and runs rough under mild acceleration. The dealer replaced the plugs, wires and reflashed the ECM but still didn't fix the problem. They say it has to show a code in order to find the problem. Any ideas?

RE: Poor performance - Dealer can't fix
 

My 92 was running like crap and it turned out the timing was slightly off. Maybe check that if you haven't already.