Fueling Problem on 2004 GMC Canyon

When fueling up I can only trickle the gas in. Seems like there might be a relief vent plugged or something?

Asked by for the 2004 GMC Canyon
Customer Concern: The fuel tank is hard to fill, fuel nozzle clicks off easily. The customer has owned vehicle since new. Powertrain Control Module (PCM) code: P0442. The fuel cap seal looks poor.
Tests/Procedures: 1. Replace the fuel cap.

2. Check fuel filler neck seal surface.

3. Check the evaporative canister and evaporative vent solenoid with hose for signs of dirt that may be causing the hard fill complaint and/or the PCM code.

4. Check with customer regarding method of fueling.
Potential Causes: Fuel Cap
Vapor Canister

Tech Tips: NOTE: A special policy exists, #07012, regarding the fuel cap and an extended warranty, 10 year/120,000 miles.
Diagnostic Codes: P0442
3 answers
There is a vent valve part of the evaporative emission control system that could be the problem. Does it only happen with one particular gas station brand, perhaps try using a different brand of gas for one fiill and see if it fills any different.
Had the same problem... I just pulled the nozzle halfway out and was able to fuel wide open.