I had the same issue with my 2001, and turned out to be the purge solinoid, which is the black box you find when you drop the spare tire I believe, I know its in that area for sure. Could be something else, but that was my problem, good luck.

Ok, there's another solid idea to test out. Any idea how I can go about testing to see if that's the cause? Short of replacing the solenoid, that is?

There's gotta be a spec somewhere that tells what kind of resistance you should get across a good solenoid. But....maybe Alldata.com or the Chevy house? I guess you could check it and if it reads open line or 0 ohms you'd know it's bad but the specified resistance could be anywhere in between.

Alright, I'll go off that and see what comes up. Thanks for the help so far, all!

Feel free to chime in anything else if you've got any ideas.

In the big line coming from your fuel filler there's an anti-rollover check ball in the steel section. filler>rubber hose>steel section>rubber hose>tank. Maybe it's stuck down? That ball keeps the neighborhood kids from pilfering your gas too.

Thank you for that tip, I'll check that tomorrow, as well!

Had this problem on my 2001 4x4 Blazer about 4 years ago. Replaced the purge solenoid and had no more trouble filling the tank.


Blazeme

So..I have a weird question...maybe it's weird.

I see there is a purge solenoid and a vent solenoid...people have used the term 'purge solenoid' on here, referring to the part under the back of the truck by the spare tire.

So...what is the 'vent solenoid'? Is that the part up on the engine?

The purge solenoid is on the engine. The vent solenoid is what is under the back of the truck.

So, am I understanding that people are suggesting I check the vent solenoid, then?