2001 gp 3.8L GT non-supercharge,130k. got rough idle and hard to start engine when it is hot. At lower speed(<40mph), sometimes engine speed drop to very low(<500rpm) and jump back to normal if I release gas pedal suddenly. Once in a while I got dead engine at red light.
New IAC and MAF. I unplug the power supply of IAC and manually adjust the length of IAC and start the engine so that the idle is 1500rpm, then I plug the power supply but nothing change. I think normally IAC should adjust the idle to 800-1000rpm. If I stop the engine and restart it, the idle will be back to normal range though still fluctuating. Does anyone have similar problem before?