if you over fill or top up your tank after the pump shuts off automatically gas gets in to the vacuum system and you will get a CEL. usually happens on long trips because like me you want to squeeze every drop in there before you leave lol. if the pump stops i stop and ever since then my truck has been great

 

I've never had that happen or heard of that. I put 2.50 more in my blazer today after it stopped. on my dodge and old jeep I have it overflow. Guess Im lucky.

 

Marx, that sounds like a feasable answer to the question. I do like to top off. Guess I'll try resisting the temptation on future visits to the pump. Thanks