The higher your rpm's, the more the alternator is turning therefore putting out more amps. When your idle drops too low, your lights will dim because of lack of output from the alternator. Check your IAC, and report back.

 

alright when i get a chance im going to check the idle air control but i dont think thats it, i think because at night with the extra load on the alternator with lights, heater,radio etc...that the alternator is going but ill take it to advanced when i get a chance and have them do an electrical diag

 

any CEL's? i had an ecu go crazy on me before, caused a low idle and all kinds of driving issues.

 

not until last night...threw a 22 again...but i have had that code come up before...vtec oil switch...but it went off when i restarted the car...i dont know it didnt do the idle thing last night just threw the code