couple days ago an alert flashed up to check the gas cap. I stopped and made sure it was tight. Didn't see that message appear any more but about 2 days later the check engine light came on and has not gone off. I rechecked the gas cap as instructed by the owners manuel and even done a gas treatment in a new full tank of gas but it still is on. Any suggestions on what it may be?

 

get the code scanned and go from there.