Q: Engine check light, rough idle, loss of power.

asked by on August 29, 2016

My name is john. i own a '07 kia optima ex v6 in excellent condition,always dealer serviced in the 4+ years i've had it. But sporadically over the last year or so, the wife or i can be driving along on the hwy or in the city, then all of a sudden the check engine light will come on and the car will start loosing power,shudder and barely make it to the shoulder or curb. Once in park,it is still running rough at idle with no throttle response. If we turn the car off for a couple of minutes then restart it,its like it never happened although the check light will still be on and eventually go out by itself a few minutes down the road. The car has had a new timing belt at 115k, major tuneup, and a new purge valve. A friend suspected maybe a bad MAF Sensor since i at one time had a K&N air filter. I've since cleaned it twice and noticed a slight improvement. Could that be my issue?

My car has 135 miles.
My car has an automatic transmission.

Hello. If your filter is over oiled and the oil got onto the hot wire of the air flow sensor, then that can cause it to burn out. A scan tool could be used to check the reading of the sensor to see if it is failing. Scanning the computer for codes would be a good idea anyway since the Check Engine Light has been coming on. I have also seen the throttle bodies fail on this engine as well as the variable valve timing actuator. These may need to be tested once the other components are ruled out. If you want to have this repaired, consider YourMechanic, as a certified mechanic can come to your home or office to diagnose the loss of power and Check Engine Light to have this correctly resolved.

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