Hyundai Repair: Sonata fails to start after fill up., fuel vapors, purge valve

Question
After filling up my 2002 Sonata will not start or will start for just a few seconds and then shut down.  Hyundai is baffled.  Last fill up it wouldn't start, but in 15 minutes it did and the started all through that tank of gas.  Is this a vapor lock or an ECM problem?

Answer
Most likely, your purge control valve is stuck open.  Normally, when the engine is off, it's shut.  If it's open when fueling the vehicle, this will allow fuel vapors to be pushed from the fuel tank through the purge valve into the intake manifold.  Then, when you attempt to start the car, the engine is flooded.  To repair, replace the purge control valve.