Q: Why does the check engine light comes on and off

asked by on December 01, 2017

I had a used engine put in. Check light came on when I got it. The diagnostics reported transmission solenoid, we replaced.

The check engine lite comes on and off now. I was told to keep driving it.
The car seat buckle light makes noise when u don't buckle up car seat, that is giving me problems...

My car has 37000 miles.
My car has an automatic transmission.

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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