Venting the G2 tank prior to filling

My tank hasn't SPOUTED gas since I had the original rubber-gasketed filler tube and electronics replaced like mid-2004. It was a STB that said my VIN range would get both while newer cars got just the tube.

Back then, there was NO air getting around the nozzle while you pumped, so when you pulled it back out sometimes you had a gusher.

While I can get still get an occasional small blowback now if I'm not careful, I'm surprised ANYBODY with a post-2004 is able to get that kind of action...

 

I also read Edthefox5's suggestion and feel that it has merit. He insists that it works consistently. The method that has worked best for me is to put the nozzle in and pump at high speed. But that doesn't work consistently. I intend to try Ed's suggestion. However, it may be another two weeks or so before I need to fill up again.

I'll report back when I do.

 

Mine vents well enough around the filler without having to wait. I can hear the air escaping as the gas goes in.

Tom

 

Yardman--you might want to read "No Fix For The Prius Gas Tank" in the Knowledge Based section.

 

I filled-up this afternoon using the prefill vent procedure. After removing the gas cap I waited approx 3 minutes before starting filling. I was able to put in about a half gallon more than I consumed; however, I know that that tank started at least 2 gallons short of true full. Sooo, I conclude I didn't get any benefit from the venting.

I will try it again on the next tank but am doubtful that I will have positive results.

 

Could be, but I've never had the slightest trouble with refilling, except for two times with bad pumps. For me there is no reason to try any of the fixes.

Tom

 

I pumped 8.2 gallons and had 2 pips left before filling. Based on mfd mpg I should have used 7.7 gallons.

My gas gauge appears to be relatively consistent on number of gallons used when the first pip disappears. When I have known the tank is full (i.e. fuel level seen in filler tube or tank burped) I will get 170 to 180 miles to losing the first pip and lose the next two pips in about 30 miles. That was one factor in my estimate that the tank was at least 2 gallons short of full since I got less than 100 miles to losing the first pip.

I have averaged 47 to 48 mpg fairly consistently over the life of the car (~72k miles) thus my estimate of about 2 1/2 gallons to the first pip drop. My driving is mostly in heavy Southern California traffic which pretty much rules out p&g as a normal routine.

 

My last 4 tanks had only 1 pip left and I put in 11.625, 11.59, 11.61 and 11.62. I pump it on slow speed and top it off after the pump auto shuts off. I only had a blow back on my first fillup when I just bought the car and didn't know how to do it right. Once it stops I top it off and I have not had a problem since my first fillup.

 

Thank you. I tested it for a few months before posting here. I was excited as it was getting irritating. Multiple clicks off..then sometimes OK..unable to fill....(always same station) and 2 fairly large gas belches. But my system only works if followed exactly.

*Let vent.
*Pump at slowest setting.I'm talking crawling. I use a small block of wood about 1 inch thick that I stick under the handle as in Florida all handle catches are removed. Probably breaking another law here...outlaw.
*Hang up first auto click off no matter what the gallon usage says as after a few fill ups it will calm down and fill up completely & now it fills all the way up. Full pips. I think the secret is really slow filling too. Which is hard to do without a mechanical device holding the handle.
* And a personal favorite..maybe it has something to do with it not sure but never ever let the tank go below 1 solid PIP. I usually hit it at 2 but sometimes I let it go till its just moved to the last PIP. Running any car low is bad but it might be the worst thing you can do with this car & its bladder.

Try these tactics for a while.

Has not failed since not once. Been quite a while now. Which is really great because after the last gas belch I was thinking of selling it as it was getting stupid. But now liking my car again.

 

Yes, your idea of venting-while-filling is discussed. A poster describes his removal of the rubber gasket as his solution.Personally, I set up a small flexible piece of plastic tubing, which I managed (with great difficulty) to insert along with the gas pump filler nozzle (thus bypassing the rubber gasket). It worked OK, in that I managed to get 9 gallons of fuel into the tank (the most ever for me). It was not a practical solution, however.

 

In 30k miles I've not experienced the dreaded fuel belch and/or inability
to completely fill the "tank". I am not particularly careful or consistent
in how I fill either; sometimes fast, sometimes slow. Most often I don't
top off, sometimes I do. All in all, I feel blessed.

Nonetheless, this condition causes me concern. I read every fueling
issue related thread because I fear the symptom can appear at any
moment and being familiar with the issue and the various techniques
put forward to avert it may save my bacon on some dark and stormy
night or when far from home.

That said, I'm beginning to wonder if the problem isn't related not to
the filler neck/pump nozzle interface, but rather some blockage or
improper valve sequencing in the known not to be essential for a AT-
PZEV rating, Rube Goldberg-esque plumbing in the fuel tank cum
bladder vapor control system.

(See http://www.autoshop101.com/forms/Hybrid13.pdf for details)

This I find less than satisfactory because I can't see the average
dealer technician being able to diagnose and remedy the situation.

With the exception of this issue and one's connected with the 12v
battery, I think this is a wonderful little car and overall I'm very glad
that I drive one.

Such is life near, but after the 2010 models no longer exactly on,
the leading edge.

 

Whew! I had to take a breath just reading that sentence!

But you may be closing in on the cause. Connecting your thought with Ed's solution, perhaps some Prii have a valve or valves that are slow to open or close due to back pressure or some such thing. Give the tank a few extra seconds and the system's problem resolves itself.(?)

Again, Ed's method is worth a try.

Oh, I meant to add that I think your Prius with the matching red wheels is fabulous and unique. Very creative!

 

Very true. As I wrote it, it seemed to have a writhing life of its own.
I considered doing a Hemingway on it and cutting it up into shorter
sentences. But as looked at it, it seemed to structurally self-reference
the byzantine twists and turns of the vapor recovery system. In the
end, I elected to let it stand in its Faulknerian resplendence.

I think you may be onto something. Neither Ed's nor my comments
seem to have the legs to stand alone. Together they do offer a plausible,
if unprovable, proximate cause.

True again.

Thank you very much. We've not seen another even remotely like her.
Amapola's flamenco dancer inspired habiliment is most definitely a work
in progress, with a number of false starts and dead ends. Further
additions/changes are in the works; some slowly moving to completion,
others at least contemplated for when $$$ permit.

 

My MO of gas fill-up is: when I exit the driver's seat, I take the cap off the tank, first thing, then proceed to put cc in gas pump and go thru charge details, then hit button as to what octane I wish, then put gas hose into car's tank opening.
I stay with the gas pump handle and fill FAST, until the first beep, telling me it is full, I disengage at that time and put hose back into standing pump. I NEVER top off---------and I have never had a blowback and my gas tank is filled to my satisfaction.
But, then.....I'm just a girl.
(being facetious)
:yawn:

 

Zonie911,

Based solely on the fact that you drive a Prius, I would say that you are
at least a sensitive, intelligent young woman.

And hey, who ever intimated that inquisitiveness, ingenuity, and problem
solving are gender related either way? :frusty:

As my Grandmother used to say by way of encouragement to grand
daughters, female athletes and politicians, etc, "You go it girl! Go it!"

:cheer2: Girl Power! :rockon:

 

Thank you so very much for your kind words, but hey.....I was being facetious. It's hard to tell in black and white type sometimes, isn't it?
I'd vote for you, Rokeby, you're a good person.

:drama: