Filling up / venting problem

The last 2 times I've gone to get fuel it seems like the filler neck on my gas tank isnt venting properly. Kicks the pump off after a few seconds.

First time it was below freezing and I had just washed my truck plus a station I dont usually use. Figured it was isolated incident. Today it was a different gas station, truck is dry, 50 degrees out.
When I'm filling up it seems like there is almost immediately a backwash coming back out of the tank gurgling and bubbling and kicks the fuel pump off.
Anybody had this issue?

 

There have been several threads on this. It's usually an issue with the rollover valve, and it is frequently caused by people "topping off" after the pump auto stops. Screws with the fuel evap system and winds up making it hard to fill the tank. Usual solution is a new fuel tank.

 

Do you typically top off when you fill up or let it kick off and leave it alone? There are a few threads about the rollover valve or the emissions evap canister having issues if you top off frequently. Sounds like it’s either a trip to the dealership or using a borescope to check if the rollover is stuck.

 

First of all thanks for the quick replies guys. Honestly my tank is rarely full, I usually dont top off or try to spend another dollar at the pump when I do fill up. Damn its irritating when you've gotta pee and you have to tend the pump handle. Well I've got maintenance coming up so I guess I will have them take a look. Hopefully not a new tank issue. That would kinda suck.

 

Rollover valve in tank or Evap. vent valve

 

Any chance you got an extended warranty that would possibly cover it?


Wondering if not fully filling might have opened the door to condensation that could cause corrosion of the same components that get finicky when overfilled? IDK, just spit-balling here.

 

No dice on the extended warranty. I've only got 32k on the truck but it's an '18 so I'm sure I'm probably screwed on that unless missouri has some emissions law like california (researched other posts).
As long as we are spitballing here tho... during the last cold snap here we regularly saw lows in the teens and single digits. Truck never failed to start, but struggled and coughed to life on the coldest mornings. I know there is a random air purge valve in the fuel system, but somehow I doubt this would affect fueling issues. Figure I'll let the stealership take a look and just expect to prob buy a borescope and have a tank dropping project. Sure as hell not paying 2k for a tank. That's ridiculous. Not before I try to put a lil southern engineering on it first.

 

Call the dealership - they extended the time on some of the warranty periods due to covid, so it’s possible you’re still in if under the mileage.

 

Has anyone figured out a bypass to this feature? What’s really odd is that my truck only does it every couple of fill ups lately. The valve must be getting stuck only sometimes, maybe weather related?

 

I there any way to "defeat the system"..?

I would love to plug in a full 38 gallons in the tank rather than 28, 30, 32.

Is there a way to bypass all of this CARB/EPA stuff?

*asking for a friend...

 

I don’t think it’s weather related. I just filled my truck yesterday when it was about -10F and no issues. It’s been between -20F and 10 or so here lately. There’s a lot of people with tundras from Alaska or Canada where it’s regularly colder and no widespread issues that I’ve heard of.

 

I went back to finish getting gas tonight. (I had to piss like a racehorse earlier and didnt have time for that pump kicking off bs) I was able to fill up with the pump set at the lowest setting. So now for my dumb question. Forgive me. Did my 2.5 gen tundra used to have a small disk like 'flapper valve' at the top of the filler neck? Or is it just on my other vehicles? Not something I really ever paid attention to. It sure as hell isnt there now.

 

Nope. Doesn't have one.