Top off when filling?

You have just been lucky. With a new car. Soon when you do that you will end up dumping a half a gallon of gas on your shoes. Do that a few times and you'll end up at the dealer with a warranty voided recovery tank from gas contamination. I hope no one listens to your advice.

 

If I could get 500 miles out of a Prius tank. I just looked at my mileage log; the best I've ever done is 460 miles. My typical tank is about 350 when filling at one pip.

On a side note I wouldn't drive the Prius anyway since my wife drives it for her stop-and-go commute. (7 miles ~ 45 minutes)

It would be illegal for Toyota to have a purge button on the Prius. This would defeat the Evaporative Recovery System required for gasoline cars. Diesel fuel is far less volatile than gasoline so diesel vehicles do not have EVAP systems. (This is why diesel pumps are always so nasty. Diesel takes hours to evaporate when spilled while gasoline will evaporate in minutes)

I pump at the same pump most of the time. I have filling issues about 10% of the time. Most days it will pump 8-9 gallons with no problems. Other times it only take one gallon then clicks off. (again from one pip)

Once the Prius bladder just would not fill. I struggled to get 3 gallons in with it clicking off every couple of seconds. I then moved up the the next pump with the same results. I put a total of 5 gallons in between the two pumps before giving up. I drove away with the fuel guage reading full but it dropped 2 pips within a mile of driving. I then stopped at another station and put another 3 gallons in. THREE pumps and at least a half hour to fill my tank. I personally believe that gas pumps have little to do with filling problems, the variation is in the Prius bladder.

 

Unfortunately, all too true. there's still got to be some way to improve the pressure equalization in the system and not bypass the EVAP system.

To me, this is just confirmation to me that Toyota has a design flaw in the fuel system. That's not to say that the system isn't working as designed, but it is to say that when some users have regularly occurring issues while others don't that there's something not quite right about the system. For something "simple" and ubiquitous like a gasoline fueling system (they've been on every gas powered car since day one) the user shouldn't have to stand just "so", worry about the alignment of the planets, or anything else. I do hope that they addressed this in the 2010 model.

 

Word is on the 2010 Prius thread is that the bladder is gone in the Gen 3.

 

EDTHEFOX - who asked you? everybody has got freewill. i impose this on NO ONE.

mind your own.

 

Not sure I follow this. What do you mean by this?

 

Why would he spill a 1/2gal? Contamination to what?

 

charles - let me explain this to you. when i filled up conventionally before, meaning, fill up and stop in one or two clicks, i would only get max 80 miles before the first pip went away.

then one day, i decided to fill up as much as it can take. while my comment was kinda vague, i mean i fill up now until it can't take anymore fuel. meaning one, five whatever clicks past full.

to comment on edthefox's comment, i have no idea since the entire fill spout/tank is meant for fuel anyways.

again, like the rest of the hypermilers that pump 50+ psi into their tires, i'm NOT telling you to do this. it's just merely what i have tried.

 

It is very true you have no idea. The entire fill spout area is not meant for fuel. The dam around the fuel spout is meant for fuel vapor. Vapor. When you over fill gas will eventually gush out of the spout and then it runs into the vapor recovery area contaminating it. Multiple gushing episodes could contaminate the recovery system. The car will then throw a check engine light and this car unlike any other you have owned should not be driven far until any check engine light is read. But even if you clear this code it will come right back until the recovery system is repaired. The bladder tank has to be replaced as a unit. The car dealer seeing this particular code will void your warranty as you have obviously and repeatedly overfilled your gas tank.
Its been discussed here many many times.

 

No, it is not meant to be filled with fuel. Doing that saturates the vapor recovery canister, which prevents it from working properly and greatly increases hydrocarbon emissions. It is also then possible for fuel to spill into the space between the bladder and the outer tank wall, and eventually damage wiring and/or the outer wall. Replacing the fuel tank is about a $1500 job. See the following thread and the embedded links for details:
http://priuschat.com/forums/care-ma...56-fuel-tank-top-off-bad-im-now-believer.html

 

Here you go:

http://priuschat.com/forums/prius-technical-discussion/30593-gas-bladder-exposed.html

 

I wrote the TrueDelta survey. My reason for going to the second click was to get a more precise measurement of MPG, in case the first click was a fluke. If the tank was full with the first click, the second will follow quickly. Less chance of two fluke clicks, and didn't want anyone to overfill, so I didn't advise going to the third.

 

Here is a picture of the fill neck with the two tubes at the 11:30 o'clock and 12 o'clock position where fuel could get into the charcoal canister:

http://tech.bentleypublishers.com/s...load/122-38805-374306-7213/prius.fuel.cut.jpg

I suppose if one force feeds the gas so the level reaches those high outlets, fuel would contaminate the charcoal canister.

It also seems that the nozzle shuts off when the fuel reached just slightly higher than the nozzle tip
http://www.answerbag.com/q_view/137434
In that case, the fuel is withing a few inches of the filler mouth; only a few ounces if it works properly

 

I have replaced many charcoal cannisters due to customers reluctantly admitting to overfilling/several clicks their fuel tanks and then claiming they couldnt pump fuel,I had a prius last week where the customer claimed he couldnt fill his tank,after confirming that his sender and gauge were correct i found the fill neck filters saturated with fuel,he did admit to overfilling his tank more than several times.I wouldnt recomend going past one click of the pump.

 

Do you have a picture of that fill neck filter location? And, where exactly is the opening located where the fuel would get to it?

http://tech.bentleypublishers.com/s...load/122-38805-374306-7213/prius.fuel.cut.jpg

http://tech.bentleypublishers.com/servlet/JiveServlet/download/122-38805-374209-7210/valve.jpg

These show that there are two tubes at about the 12 oclock position of the filler neck. The fuel would have to reach that level to enter these filters, no? And, the fuel would be coming out the filler neck to the ground?

Or, is there another opening someplace not on these pictures where the fuel would enter the filters?

 

If the pump isnt in the fill neck all the way the fill neck can and will fill all the way to the top before it stops,it might not always spill out onto the ground.this may be on the extreme side,but if the tank is functioning properly fuel shoulnt leave the tank into the fill neck?so what else could cause fuel to get in the fill neck?

 

No. Listen....read up some more about this. There's a million posts about it here. We've been beating this dead horse now for quite a long time. It doesn't matter if the pump is in all the way into the neck...half out of the neck..all the way into the neck..upside down in the neck. If you insist on topping off the tank gas eventually when you least expect it to (like your dressed up with real nice shoes on) it will FORCEFULLY expel some gas (my first & last looked like maybe a quart) back up the fill neck. I don't care if you have a hermetic seal around the filler neck gas will fall to the ground..and soak the neck area and eventually make its way into the recovery vapor system contaminating it and maybe get on your nice shoes.

And the other poster right before you wanting to know exactly where the entry points are around the filler neck for vapor recovery. It doesn't matter much where the vapor recovery ports are around the neck when you hit it with a quart of gas fuel will get in there and ruin that canister.
Hang up the pump on the first click.

 

Will The New 2010 still have the bladder??
Thanks

 

No it wont