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Q: My car idles sometimes and there's a problem with the spark plug and coil all the time

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Me using the car fron 4 months now from 2 week came problem with idle of car in lower gear and i went mechanic then change one coil after 3 day came with same problem went there then change another spark plug coil and that time also plug changed tbey are very dirty.after 1 week feeling the same problem.i dont know what to do..

My car has 500000 miles.
My car has an automatic transmission.

A: Idle issues can be caused by a few differ...

Hello.

Idle issues can be caused by a few different things. A few common causes are faulty coils, or an issue with the idle air control valve. The ignition coils are the components that generate the engine’s spark. It may be possible that they are failing and causing the misfires. If you have already had to replace two of them due to failure, it is likely that the other two will also need to be replaced. An electrical resistance test can determine if they need to be replaced. I would also look into the idle air control valve. The idle air control valve is the component that is responsible for maintaining and adjusting the engine’s idle speed. If it fails or has an issue it can cause an irregularly high or low idle, and in some cases even stalling. If you are unsure I would recommend having a professional technician, such as one from YourMechanic, come to your location to determine what may be causing the idle speed issues.

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