I am having problem after filling gas, always need to turn the ignition twice and will not start smoothly, any clue?

Is this problem only when filling the car with gas?

Questions to help narrow it down:

What if you just stop and shut down the motor for 5 minutes. Does it still happen? If so then I would think that the filling is incidental to your problem.

If not then try shutting it down and just removing and reinstalling the gas cap. Does it still happen? If so then I would suspect that it has to do with you vapor recovery system. It's over my head.

If not, and it only happens when you put gas in, then I would try a couple cans of STP fuel treatment and run the tank nearly dry between fillups. There may be just enough water (condensation) in there to be a problem when filling.
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Nathan Valles, Black 855R, Tint

It might be water in your gas tank. I had a similar problem occur a couple of years ago as I was filling my '89 740. (I think I had water that settled in the bottom of the tank and filling the tank mixed it up with the gas.) The engine ran very rough for a few minutes then it smoothed out and ran fine. I added a can of gasoline additive to the tank that removes water and have not had a problem since.

Yes, it only happens when refilling, thank you both for the tip, will try the suggestion tomorrow. :)