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Q: Hard acceleration and hard braking when stop

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I’ve noticed that after I’ve driven kind of spunky like, there’s hard acceleration from a stop position and hard braking… When coming to a complete stop, my car’s RPMs go rather low, almost to 500 (where that gap is) and I feel a slight vibration, plus the car seems to shake a little. Then it seems like the car recognizes that they are low and there’s suddenly a boost and the RPMs go to normal position. It idles when it goes down to 500 RPMs and then bounces up to normal.

A: You may be having a normal condition. When ...

You may be having a normal condition. When you accelerate hard, you are dumping a large amount of fuel into the engine and then stopping quick and shutting the throttle. You still have all that fuel in the engine and it has too much fuel for the engine to idle good for a few seconds. If you have a Check Engine Light or feel the idle is getting too low or it stalls, then you should have the system checked by a mechanic.

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