check engine light continuous, 2009 cayenne
 

The last time this happened it was a clogged air filter but I have a new one in. There is 1/4 tank of gas and cap is tight. I filled it up just now and light is still on. Car is running fine and I hate to make the 75 mile trip to the dealer. I assume that if I had a problem with my previous gas fill up the light would have gone on before. Any suggestions/
Thanks
Fred

Took it to autozone to scan it and got a P0431 which sounds expensive