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Check engine lite

I have an intermitten check engine lite, seems to be somehow related to the gas. More often than not, whenever I put gas in the car, soon after the status of my check engine lite changes, either it comes on or it goes off. I know I should have it looked at but I was wondering how putting gas in my car can affect the check engine lite. (The gas cap is always checked).

You probably have a problem with the evaporative emissions system on the vehicle. This is the system that prevents gasoline vapors from polluting the air by capturing the vapors.
The gas cap is the simplest part of the evaporative emissions system. After that it gets much more complicated, and the problem could range from a bad seal on that cap, to a stuck solenoid valve in a vapor line, to a contaminated carbon canister, to…

But, rather than going with my guess from afar, you need to take the vehicle to a place like Auto Zone, Advance Auto Parts, O’Reilly, or (possibly) Napa for a free scan of the trouble codes that have been stored by the OBD system.

After getting the codes, come back to this thread and post the codes for further guidance.
Bookmark the thread so that you can locate it again.

CEL’s can be annoying but that does not mean you have to start throwing money at them…

gas cap checked? Did you check the gasket…depending on age it could be cracked.