Q: Check engine light

asked by on January 05, 2018

Check engine light came went too two different mechanics both said they don’t see anything faulty one of them said it could be small leak somewhere usually gas cap but doesn’t seem that could be it other said maybe changing sensor which was changed the o2 went off now came back on 4 days later not sure what else I can do car is not running different

My car has 51000 miles.
My car has an automatic transmission.

The cause of the issue would depend on which trouble codes are stored in your vehicle. If you have a small evap leak on your vehicle I would recommend having the vacuum lines check to determine if any small cracks like that might enable a small vacuum leak to cause a check engine light.

Generally, the check engine light comes on when something fairly serious is going on with the vehicle. This can happen for many different reasons such as a faulty mass air flow sensor, a faulty O2 sensor, a bad catalytic converter, bad spark plugs or spark plug 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. This will allow a mechanic to determine more specifically what to look for in diagnosing your vehicle. 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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