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Q: Low rpm idle

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So when I start my car my rpm idle looks fine but when I put it drive and start driving around and come to a complete stop my car rpm idles low then it suppose to be and the engine stalls a little bit and it goes back to normal. I change out some spark plug and it helped a little bit but it still has a low rpm idle and I thought it was the ecu because I made a short circuit when I change out the battery a couple days ago

My car has 90391 miles.
My car has an automatic transmission.

Since you had the battery disconnected the computer needs to relearn the idle again. I would recommend having the throttle body cleaned and then the throttle relearn process done so the idle can stabilize and be relearned by the computer. You will need to clean the throttle plates and disconnect and reconnect the battery again to relearn the idle.

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Hi there. It sounds like you may have a dirty or failing idle air control valve. The idle air control valve monitors the air intake as it is mixed with fuel prior to being injected into the engine at low speeds and at idle. This valve is controlled by the vehicle’s computer and will adjust idle speed based upon other measurements such as engine temperature, intake air temperature and electrical system load or voltage. If you had a short circuit issue with the battery, the ECU may be damaged; so keep an eye on your car’s check engine or other warning lights.

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