What would make the car run overly rich at idle, esp if I rev a little and let off? I have a new 02 both stock comp and piggyback MAFT has same problem even after the 550 injector tune down. Seems to run rich and smoke =( is there something elce that would be a factor? Also the car idles fine one minute then starts stumbling a few minutes later when just left alone is there a link between the 2? I think it stumbles because it suddenly runs rich but I dont know why it would change like that for no reason.
