Q: My cars RPMs rev up and down

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Okay. When I start my car, it starts fine. In park, my RPMs will rev up all the way to 2. And then back to 1. Quickly and doesn't stop until you put it in Drive. When I'm in Drive and actually driving the car, it will rev up to 2 the whole time I'm driving. It almost wants to drive itself. Meaning if I'm not pressing the gas, it will accelerate to 40mph and I'll have to ride the brakes almost. Why are my RPM raving up.

My car has 220000 miles.

Hello, and thank you for writing in. Typically when the engine behaves like this, you are looking at an air issue. You will want to focus in on the air intake, mainly the throttle and throttle position sensor. You may also want to look into the exhaust and the oxygen sensors. You should then look into vacuum leaks which can be tested relatively easily. From there you will want to look into the fuel pressure and the fuel injectors. If this system checks out, then you can turn your attention to the ignition system. Only further testing will tell. For more help with diagnostics, contact our service department to schedule an appointment.

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