P0356 after filling up tank

After my last three fill-ups, the truck has thrown a P0356 code (cylinder 6 ignition coil).

1st time: within 10 miles of filling up
2nd time: within 40 miles
3rd time: within 5 miles

I cleared the first code, the second one cleared itself, and I just got the third one.

I’ve never overfilled the tank and I always secure the gas cap.

Gas was from two different stations, but same company.

I’ve checked wiring under hood and everything looks great.

I bought the truck with about 3000 miles on it and now it’s just below 10000.

This last time, the engine sputtered slightly while starting to descend a hill right before the code. The second time, it may have done the same thing going downhill except the code was already thrown a few miles before. The first time, I noticed no symptoms.

Bad ignition coil? Something wrong in fuel delivery? Other?

 

Next time the code is set I would take it to the dealer and not delete the code and have them look at it under the warranty

 

move the #6 coil pack to another cylinder and see if the code follows the coil.

 

Can you say warranty! To the dealer with you. Don’t be messing around with something under warranty