I have a 2010 Honda Accord EX-L and the check gas cap light comes on. I bought a new gas cap. It will go off after several miles and then back on.
What could be the problem now?

 

the check gas cap light sets for a large evaporative emission system leak. The car sees the fuel level change when you refill upon start up. The evap monitor runs a leak check and if it detects a large leak...thinks you left the gas cap off....but the leak could be anywhere in the system. You could have the fault code read with a scan tool and try to follow a diagnostic procedure for that code...or Have a shop leak test it.