Gas tank

not so far, i'm at 20,000. what is a pop off?

 

Not for me either, and I'm at 55,000 miles. I have run into a couple of bad filler nozzles, but that's not quite the same thing.

Tom

 

intersting. are you going back to the dealer for another one? maybe the back pressure is affecting the gauge sensor as well?

 

The problem is well known and commonly referred to as the "gas bladder problem". This is the first time I heard of the explanation being a bad valve. Usually people say it's the bladder got more stiff sometimes and more flexible some other time. I like the valve explanation much better though.

 

Hi I'm kinda new to this site but,

I just had this problem today! I'm relieved and troubled at the same time that others have experienced this issue with the bladder gas tank. My trouble was as soon as I started to fill from empty (9.5gls). I had to squeeze very carefuly for the entire 9.5gls. No other problems as a result of this condition, so I'm hoping that it was the pump nozle rather than the car. I have never seen a bladder filled gas tank before so this is wierd to me, not sure why its used and are they being used in other vehicles?

 

If the burping problem is in the pump, the most likely cause would be
some blockage of the tube that returns the displaced air in the Prius'
tank to the underground tank:



A second possible defect in the pump handle is a small plastic valve
that lifts as the displaced air escapes the gas tank. When the air stops
flowing, the valve drops and signals the pump motor to stop. If the
valve is worn it can signal prematurely.

The only "fix" in these cases is to use a different pump.

There is some variation in the size of the gas bladdder:



There is a Service Bulletin on the Gen II fuel system:
View attachment T-SB-0163-08.pdf

For a complete run down on the Gen II fuel and evap system, go here.

There have been many, many threads about this issue.
Use the Search Tool with "burp" to find them.

Hope this helps.

 

The bladder was used to minimize the exposed free surface of the gas, thereby reducing evaporation and resulting emissions. Fuel bladders have been used for a long time, but not commonly in passenger cars. Typically they were used to reduce the risk of fire in crashes and to make self-sealing fuel tanks for military aircraft. The new 2010 Prius no longer uses a bladder.

Tom

 

even though you are out of warranty, because they already replaced it once, i would think they will take care of the problem no charge. all the best, let us know!

 

Ok..... I filled the tank twice since this post with out problems. I'm thinking that the bladder tank may cause some already sensitive pumps to react worst than without bladder. This I conclude from useing the same pumps for yrs with a Focus and somtimes felt that some pumps were more sensitve than others cause they would shut off prematurely.

 

This has been my experience.

Tom