Every key turn start up is quick and smooth except for when I fill the car up with gas. Get back in car and turn key for a slow hesitating engine start up. Once starts is fine again until next gasoline fill up event. Problem only occurs following gasoline fill ups.
My car has 70000 miles.
My car has an automatic transmission.
The most common cause of hard start after fill up is going to be the excessive gas fumes during refueling the vehicle will flood the engine causing the hard or no start. The excessive fumes will normally be stored in the emission control system carbon canister and then when you get into a cruising speed the purge control valve will open and the engine will use the excessive fumes to run the engine. This is what should happen but in your case the purge control valve is not holding back the fumes when you refuel and leaks the fumes into the engine when it should not be causing the over rich fuel condition. The purge valve is mounted on the engine near the fuel injection system. The purge valve should be vacuum checked for leaks and replaced if leaking when off.
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