Hyundai Repair: Trouble starting on fill up 2005 Sonata, fuel vapors, hyundai dealership

Question
I have a 2005 Sonata, and I have been having trouble with the car starting after fill up. For instance, I have to pump the gas to get it started and keep pumping it to get it going until it is running. After that it runs fine. But the Check engine light is on the whole time. I just had the air filter, fuel filter, and the spark plugs replaced under the Hyundai dealership and the problem persists. What do you think could be the problem?

Answer
I'd guess that your purge control valve is stuck open.  If this occurs, the filling the tank will push the fuel vapors into the engine, causing the engine to flood and be difficult to restart after fueling.

Since you say your check engine lamp is on, I'm curious what was done about this.  Do you know what trouble codes are stored?  Did the dealer check the stored codes?  Heck, I'd even guess that the code P0441 (abnormal purge flow) was stored.  If so, that should have made diagnosis rather obvious.  It'd probably also make me question why the dealership was busy replacing filters and spark plugs instead of addressing the check engine lamp.