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Q: Wierd rpm spike when coasting in vehicle.

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When i am driving down the road and just let the car coast once it hits about 500 rpms it has a slight spike to 1,000 rpms. It continues to do that over and over again until i give it gas again then it is fine. Thank you for you answer

My car has 131000 miles.
My car has an automatic transmission.

Your car has an automatic transmission and will automatically downshift as the speed of the vehicle slows down. This spike in RPM’s is just the downward gear spinning the motor up slightly as it downshifts. Nothing to worry about as this is completely normal.

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