We gave my son our Mitsubishi Montero Sport 2001. The last year we owned it, all the lights internal and external oscillated dim to normal. He took the battery cables off and cleaned them and now he says that he can start the engine, but it dies unless he keeps it reved up. I know that the alternator belt was loose, but hadn't the chance to tighten it. Anyone know how to fix the idling error so he can takeit to the dealer and ensure the computer is reset?