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Hi all, need some help with a car issue. I have a 2000 Civic Coupe EX. Whenever in parked position or stopped at a red light on a flat surface my car rocks gently back and forth about an inch. I'm not sure what its called but the gage next to the speedometer looks like it is revving up as it moves slightly up when the car inches forward. Car sounds like I'm pressing the accelerator. It seems like the car wants to move but it cant because its in park or I have my foot on the break. Anyone know what the issue could be? Thanks in advance.