when you turn on your headlights, rpm goes down on idle? when i idle normal without lights on, i idle at 800. but when i turn on my headlights, it goes down to 500-300.

 

should pop up to 1000-1100

 

Your idle shouldn't drop down that low. Just adjust your idle up more.

 

or check your fast idle control solenoid. that could do it too, might throw a code for that one though

 

yes it should drop
but then the engine rpms should slowly pick up again some more rpms bc of the electric load.... its called voltage regulator and the engine should compensate a lil when the rpms drop bc of load

 

the only code i have is knock sensor code. but then since i put on my chipped ecu, i have no code. another weird thing is...usually when my car is cold..the rpm is pretty high, like around 1500 - 1700, then it'll go down as it gets warmer. but when i warm up my car today, it sat at 800, then when it got warm, it went up to 1100. hahah weird.

 

?

 

it is possible that the grounds on the car need to be replaced.
that can have a bearing on your idle RPMS.
is your car idle hunting?

 

im not too sure.. but ill try and replace it.