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Q: Hi i have an 09 kia rio and my check engine light is on and the motor shakes when idling and when going around 40 mph. What could

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The check engine light isnt flashing but its on, when you start the car you notice the engine shaking more than normal. I let it warm up about 30 minutes today before driving and it continued while braking, and when you get up to 40 m.p.h it gets worse

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

Hello, thank you for writing in. The check engine light is designed to stay on constantly when there is an issue. You should start by having the vehicle scanned for diagnostic troubleshooting codes. These are codes meant to help the owner or technician diagnose issues detected by the computer. When your check engine light illuminates, there is at least one code saved. This can be done by a technician or at most local automotive parts stores. Once you know the codes you can take appropriate corrective measures. The engine vibrates and idles rough when the combustion process in the engine is not steady and correct. This may be a spark, fuel, air, or sensor issue. The good thing is that the check engine light and the codes will point you in a direction where diagnosis will be easier.

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