okay when i have my lights on, and i press on the brakes at a stop light my idle goes from 1000 down to 500 and it shakes my car badly, almost like its going to just die on me, i let off the brakes.. it goes right back up to 1000. help me figure this out, i've tried messing around with the idle a bit, now i have it at regular 1100 rpm and it still drops down to about 600 and vibrates the shit out of my car. so please help me.