Look with a flashlight to see if you can see the problem and get back to us. It could be a charcoal canister that has gone bad as well.
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Friday, August 18th, 2017 AT 10:29 PM
The first thing I would check is the gas cap O ring seal which could have broken or has cracks allowing the tank pressure to escape.
If the cap is okay the evaporative system integrity monitor assembly which is located on top of the fuel tank and must be replaced. The gas cap light will turn itself off after the pcm has ran and passed the leak test, to get it to run the leak test you would have to drive the vehicle at least twenty miles and then let it sit over night.
If after doing that the light remains on then you have an evap failure somewhere. Is the check engine light on? If so what are the code/s?I would try the drive and park routine and if it is still on the next day have the codes read, if there are no codes.I would suggest that you take it to a shop that can properly diagnose it. But in all likeliness, you will need the new assembly mentioned above.
Here is a guide to run the codes to see if a sensor problem is causing the issue.