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Q: Can the idle air control cause my engine to idle roughly?

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My 2006 2.4L Kia Optima has a rough idle. This started 2 days ago. I changed plugs and wires, still rough idle. Someone said it could be the idle control.

My car has 136000 miles.
My car has an automatic transmission.

A: Hi, thanks for writing in. Sure, the idle c...

Hi, thanks for writing in. Sure, the idle control valve can definitely cause the rough idle. Typically this will be caused by excess carbon buildup inside the throttle body or fuel injector nozzles themselves. Your 2006 Kia has multiple sensors that monitor and control the fuel system. If one of these sensors is dirty, damaged or sending misinformation to the Engine Control Module, it can cause the idle to run very rough. Some other issues that may be causing this symptom may include dirty EGR valve, air/fuel sensor or problems with the throttle body itself.

If you would like help, consider having an expert automotive technician from YourMechanic come to your home or office to inspect and diagnose this issue for you, and make or suggest any repairs as needed.

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