I drove with the gas cap not completely sealed which threw an error message.
Now the check engine light is illuminated. I filled the tank and tightened the gas cap. My thought is to run thru a tank, refill. If this doesn't work then may try a battery disconnect/reconnect.
any thoughts?

 

Get the codes read via OBDII scanner. If the code that comes up matches a loose gas cap symptom, reset the code with the scanner tool. If the code doesn't match, it could be something else you should investigate before resetting the code.

 

Do not repeatedly disconnect the battery or reset the CEL more than once. Doing so will only prolong the amount of time that the system takes to run through all the steps! Sometimes the EVAP test takes quite a bit of time. Of course that all depends if it IS the Evap system, as shemp states.