Engine Performance problem
2002 Saturn L300 6 cyl Front Wheel Drive Automatic 105000 miles
Car has a random misfire at idle accompanied by 50-100 rpm drop with no codes. Misfire gets more violent after stop and go traffic. Operates fine at highway speed with no lack of power or hesitation. However when slowing down for a stop sign or light vehicle will stall. When I attempt to restart it either will start, run rough for a second then die or will rev up to ~1500 RPM then immediately die. After a couple of minutes vehicle will start up and run fine EXCEPT for the misfire have replaced spark plugs, run a fuel system conditioner through, checked all vacuum hoses, sprayed out throttle body(but did not remove and completely clean), cleaned MAF sensor. Vehicle has pulled codes for #1 cylinder misfire that cleared itself, MAF input high that cleared itself, and IAC system RPM low that cleared itself. All codes came up after messing with system but clear out on their own and do not reappear.