Chevy Traverse Hard Starting After Refueling

HAVE A 2015 CHEVY TRAVERSE WITH A V-6 3.6 LITRE ENGINE. IT IS HARD TO CRANK AFTER REFUELING. IF YOU LEAVE IT RUNNING WHILE REFUELING, IT WILL RUN ROUGH FOR A FEW MINUTES AND THEN LEVEL OUT. BEEN TO AN AUTO SHOP WITH NO RESULTS. HELP !!

Answer: I assume when you say hard cranking, that the engine cranks but is hard to start? No that it cranks slow. If it cranks slow, that is caused by a weak battery or starter problem.

Running rough after refueling is usually caused by bad fuel, but you say it clears up, so that cannot be the case. Be sure you are not putting in E-85 gas, unless it is a Flex Fuel vehicle. If it is, and you are putting in a different type of fuel then is already in the tank. Example- if the tank of your Chevrolet Traverse already has E-85 gas in it and you are fueling up with regular gas, you need to put in more then 5 gallons so the computer can re-calculate the alcohol content in the tank now that there are two different fuels. Same goes for the other way.

If this is not the case, then this is a strange problem. The only thing that is happening when re-fueling is that the gas cap is removed. This can have an effect on the evaporation emissions system, since that system is sealed by the gas cap. I would have the computer scanned for trouble codes to see if the computer caught something.

Other than that, the loss of pressure in the evaporation emissions system after removing the cap should not have an effect on the way the truck runs, unless there is a vacuum line switched and now the engine has a vacuum leak. if you had any work done that required removing the gas tank or any work under the hood just before this problem started, then someone may have a vacuum line and emission line switched with each other. A vacuum leak will cause the engine to run bad at idle.