Gas cap hissing. Can’t barely pump gas.

[iboughtatahoe23]

2014 Tahoe Lt 178k

Changed charcoal canister. And now it’s worse. Don’t know how pellets would have gotten in the lines if I took the hoses off before the canister. Any way. This thing clicks off every few dollars and hisses when I take off the cap. I have to trickle it or use a funnel.

Some youtube videos below:
1) Gas cap hiss
2) Pump clicking off

 

[PPV_2018]

Sounds to me like possible fuel vapor issue? Did you purge the lines out when you took them off to replace the charcoal canister

Had a similar issue on a different car where the evap purge solenoid failed choked the fuel system.

 

[Fless]

If the ignition is in the off position (meaning no power to the evap system) either the canister vent valve is not opening or the evap system is somehow plugged. The system shouldn't hold pressure like that with the ignition off.

Here's some of the back story: https://www.tahoeyukonforum.com/threads/charcoal-canister.152136/#post-1935228