Ive got a 2015 XLT 2.7 Liter ecoboost, up until recentaly had no issues. But last 2 times I added gas the pump kept kicking off like the tank was full...took forever to get it full. Never seen this before? Any ideas? Its the capless style

 

My first guess :-) would be that, the EVAP system's vent solenoid valve is stuck closed or it's plugged/restricted?

 

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