Idling Problem

Well last night when i was coming home my car drove perfectly fine then i pulled into the driveway put it in park n put the e brake on my lights were still on and i noticed they were getting brighter n duller so i turned down my music and noticed the car was like sputtering and would jump and every time it did this the lights would all dim then brighten up again and the RPMs would drop a tiny bit then go back up again.

Any ideas of what this could be would help me out a bunch
Thanks

Jay

was the a/c on? that happens to my car every once and a while when i have mine on.

No the AC wasn't on

what is the idle speed? cuz when my idle speed was like 500rpm it would do that sometimes but when i adjusted it to about 750rpm it stopped cuz the engine was not making enough power at the lower speed and would make the lights dim.

ya mine revs at about 600 n then drops to 500 n goes back up again it hasn't done this ever since i wrote the first message tho LOL funny how that works