Q: Car's rpm goes up and down while idling.

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When I turn on my vehicle or have it parked, idling, the rpm gauge goes up and down, as if I'm pushing or revving the gas pedal. The car has died once since this started to occur, but I was able to start it again and make it home because it was a short distance. I checked all fluid levels and they seemed to be okay. The only one I was concerned about was the transmission fluid, it was on warm, but the color of the fluid wasn't red. It appeared to be patchy on the dipstick. Kind of brownish looking. What do I do?

My car has 157000 miles.
My car has an automatic transmission.

The power train control module controls the idle on the vehicle using different sensors and actuators. If you do not have any codes in the computer for the problem then you may have to have the computer reprogrammed per the manufacturer technical bulletin 18-13-00 dated August 2000. I suggest having the idle issue inspected by a qualified mechanic like one from YourMechanic first, to make sure there are no other possible causes for the idle problems and then have the computer reprogrammed with the dealer reprogramming scanner.

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