What in the world could block my fuel filler neck?

[MountainDont]

This half ton should have almost a straight shot to the tank. It almost has to be clogged with trash or something.

This looks like the easiest to siphon truck (still) on the road, but when I went to the gas station for the first time, I could pump 8 cents of gas before the pump handle shut off -- no matter how deep or how shallow I put the nozzle in. I got $6 worth of gas and drove home to investigate, but it was too dark.

 

[movietvet]

Couple years ago was on a long trip. I know that my 2005 Tahoe Z71 had no evap problems or tank/filler problems, because months before that I had done a new fuel pump and complete evap system, with Genuine GM parts and all had worked flawlessly for months. Wa. state Chevron pump kept shutting off. I filled slowly and moved on. Never a problem since then.

If you got no warning and had not done any work to the evap or tank system, you did not say, then try another station or another pump at same stating and see what happens.

 

[MountainDont]

I think the previous owner had this problem. It was likely one of many reasons to sell it.

 

[454cid]

I drove a GMT-610 that started doing that. It was the evap system, but being GMT-800 derived its not the same as what our trucks use. I would suspect the vent hose, which runs parallel to the filler hose, and connects to the tank and filler neck. Also, you probably have a check ball in the fuel filler port of the tank. I wouldn't think the check ball would be bad, but I suppose anything is possible. You'd probably have to drop the tank to look at it, Though.

Trying another pump, is also a good preliminary check.

 

[Scooterwrench]

My sis-n-law had that problem with her Yukon. Turned out to be the charcoal canister back by the tank wouldn't let the tank vent.

 

[Erik the Awful]

My '02 Jeep suddenly developed a problem where the gas station pumps kept kicking off unless I set the handle at a slower setting. Peering into the filler neck, it looked like someone lost a siphoning hose. Like the little flapper caught on the hose and they couldn't get it out, so they just shoved it all the way in. I just pumped slower and eventually sold it with that problem.

I'd unbolt the driver's side bed bolts and loosen the passenger side. Unbolt the filler neck from the bed. Prop the bed up and pull the filler hose assembly off the tank and inspect it.

 

[MountainDont]

Well, so far we've gotten nowhere. My previous owner thought may be wrong. And an inspection with a few probes did not encounter any debris. Maybe it is the vent. I will try another gas station today I hope. She hasn't been to town in weeks! (See my brake bleeding thread for why... what a mess.)

 

[Caman96]

Always helpful to mention what you’re working on. That being said, maybe bad evap line or canister. Maybe previous owner(s) were habitual over-fillers.

 

[rebelyell]

My example is Not a pickup and not a GM product. But it might apply here as well, dunno.

I have owned several Later Lincoln Town Cars. And we all reside in deep south.

Suddenly, I could just barely get the car to take any gas when I tried to fill up; excruciatingly slow.
It did this consistantly & repeatedly UNTIL I found the problem and remedied it. These cars have a rubber hose vent line about 3/4" that tee's into the filler neck and loops around driver side rear frame rail and then simply slips inside that rail. The ever-present dirt daubers or wasps had built a hard, bright white, mud plug into the end of the hose that was stuck into frame rail. Cleaned it out and all's good. To filler neck & hose were Not clogged; its vent was. They build plugs into anything and everything I have. I just keep a check & pull the hoses and smack em every so often to clear anything. So far so good.

Dunno how, but I also have several GM vehicles including 2 pickups, a van & old vette. NONE of em catch bugs like the town cars do.

 

[rebelyell]

Couple years ago was on a long trip. I know that my 2005 Tahoe Z71 had no evap problems or tank/filler problems, because months before that I had done a new fuel pump and complete evap system, with Genuine GM parts and all had worked flawlessly for months. Wa. state Chevron pump kept shutting off. I filled slowly and moved on. Never a problem since then.

If you got no warning and had not done any work to the evap or tank system, you did not say, then try another station or another pump at same stating and see what happens.

This is sort of a smartazz question but it's really a valid one. I was roadtripping through gorgeous Oregon several years ago. I got rude surprise late one night, just as I drove into Pendleton via Spokane, in that I wasn't allowed to pump my own gas; because of some Oregon State law I was told.

So, firesuit on ... If ya do not pump your own gas, and ya don't routinely hop back & forth across the river, how the heck can a driver know when the pump's not filling/working as expected ? BTW, We spent the entire following day enjoying Pendleton; that leather aroma of Hamley's saddlery. Then we followed the river to the sea.