Q: Check engine light (on and off) by itself.

asked by on December 26, 2016

The check engine light turns on for some time (2 or 3 months) and turns off for a week or two and again stays on for another 2 or 3 months. The car performance is good, no power failure and easy start up.

My car has 24380 miles.
My car has an automatic transmission.

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Your check engine light may come on for many different reasons such as a faulty mass air flow sensor, a faulty O2 sensor, a bad catalytic converter, bad spark plugs or wires and many other reasons. Due to the wide range of possibilities for the check engine light to come on, the best and most efficient way to narrow down the scope of what may be causing this is to have the vehicle hooked up to a scanning tool to download any potential fault codes that may have registered in the computer. I would recommend having an expert from YourMechanic come to your location to take a look at your vehicle to determine what may be causing your check engine light to come on.

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