l have a 2002 Hyundai Santa Fe. l have only had the car since March of 2007. When l drive at night the lights dim down for a couple seconds then return the original brightness. The a/c is on l do not know if that makes a difference or not, but also when l first start accelerating it feels like it jerks into 2nd gear but does not do it anymore throughout the duration of me driving. l have had the alternator checked and it is great, so is the battery. Does anyone have a suggestion? Thanks!

A problem on the 2002 that l have no answer, but believe to be a ground issue.The jerking will not happen if car is at normal temperature, worse in winter use the Manuel shift until it warms up

The lights are dimming when the A/C compressor turns on, and then when it cycles off, your lights go back to normal. Sounds like your idle is not adjusting for the added load needed for the A/C compressor. This could also cause the jerking you are talking about.