my car has a rough idle from about 700-950rpm. but runs great everywhere else. its running slightly rich and backfires sometimes when i let off. what could be the cause of this? if i turn the a/c on it sometimes corrects it, even when i turn on the lights sometimes. mods: dp, mp, trust evolution 2 exhaust, xs engineering ecu, k&n intake and filters, 9.24lb flywheel, act clutch, greddy hard piping & intake elbow, greddy pulleys, apex bov. could this possibly be a sign of worn or cracked apex seals? if so how much would it cost to have it fixed, or should i just do the whole motor? i've heard that a rough idle can have to do with the bov, or intake pressure. would an apex s-afc cure this? im thinking about taking it to KDR to have a tune up. is this problem serious? thanks !

 

It's most likely because your car is running a bit rich at idle. When you're turning on extra electrical loads, the motor takes extra effort to try to keep the idle, so your idle drops a bit.

Running rich isn't really a problem unless, it's annoyingly errantic, or bogging. An AFC would correct this, but it's not necessary.

I use one but i'm not impressed by it. I'd much rather get a big aftermarket ECU.

 

yeah, i agree about the ecu. what kind of ecu do you have? what kind do you recommend?