Multiple Evap Codes

1. I have seen a very few stories like this, caused by over filling. The excessively byzantine Prius fuel system is $$ to repair. Always stop sooner, like the dealer said. That said, be sure that the gas cap is good and on properly, as that can also set a code.

2. Not a performance issue, as far as I know. You can clear the code by disconnecting the 12V battery for a few minutes.

3. Yes, but it requires removing the entire fuel tank assembly. You might be able to get parts from a salvage yard. Maybe autobeyours.com, which is not too far from you.

 

I have always topped off or more than topped off when filling up with gas and have not had any problems yet.
Hopefully, that will not be a future problem.

 

Oh man.... It's so darn hard getting a full tank on Gen2 with their dumb bladder system and now we have to deal with this? Sometimes on really powerful gas pumps in California even when I trickle the gas in as slow as possible and try to make sure I top off but not too much I end up driving away thinking I filled the tank only to find out a couple hundred miles later that the car should of held a couple gallons more than it allowed. This doesn't happen very often, but it sucks when it does. And now not only do I have to worry about if I really did fill the gas tank up all the way, but I also have to worry if I did damage from filling it up all the way. This is so annoying! Bladder based gas tanks may pollute the air less, but they're total hell in practice. Also I've found that in 100 degree heat that bladder will hold way, way more than ever before.... So far I haven't had the bladder puke a gallon of gas back out at me like many of other people have. Then you combine that with a gas gauge that is actually a guess gauge. It's totally insane!!! I guess the only fix is to only buy 20 bucks of gas at a time... Of course on long road trips that's no so practical.

 

I suggest you don't the gas bladder: exposed! | PriusChat shows a tank that was replaced for overfill damage.

Unless a pump stops WAY short of where it should (sometimes happens), I personally wouldn't go more than 1-3 clicks past the initial auto-stop.

 

That's the problem... The guess gauge is not accurate enough to give you a sense of how many gallons your tank will hold and if a pump stops way short and you try a few extra times to keep filling it you may still roll off with room for another gallon or two. So annoying!

 

Well, by WAY short, I do some calculations from my trip odometer and MFD (that I reset after each fill). For example, if I've traveled 270 miles and the MFD reads 45 mpg and the pump stops at 3 gallons, I know that's way too early.

 

If it is possible, let the gas cap off of the tank for 30 sec or a minute before starting to fill, so that the pressures can equalize. This seems to help for me.

 

Being in the UK I do not have the problem of the bladder in the fuel tank. However I do top the tank off, and when I say top it off I mean till I can see fuel in the filler neck. This makes fuel calcs easy and accurate, and although the fuel gauge is very non linear it does give repeatable readings.

I have never had a problem in 90,000 miles, and have never had a problem with any other car with similar evap systems. I do sympathize with those in the US that have this problem.

John (Britprius)

 

I have always topped off. This last gas fill up, it was very cold, and when I filled up it made this funny noise like something dropped or gurgled very loud - this time gas did come out - so I hurriedly pull out the gas hose and capped it. It has never did that before.
This time I was able to drive 152 miles before the first notch dropped - usually it goes down one notch anywhere between 89 and 128 miles.

 

Pretty sure your non-bladder gas tank has a standard carbon filter device so when your car fills up with gas the toxic air/fumes that are displaced from inside the gas tank is filtered by this charcoal-based filter.

But when you fill your tank up to the top of the fill spout you will not only foul that system, but you off gas loads of toxic fumes both at the point where you fill the tank, as well as at the place where the displaced toxic air/fumes exits the gas tank.

For the sake of all of our lungs, you should get your filter replaced and try not to fill it so full from now on...

 

The filter is only related to regular gas tanks. The whole reason they created the bladder design was to eliminate that filter and the toxic air/fumes that exits a solid gas tank. In a bladder tank the tank collapses and isn't displaced with air. The reason your car got error codes is because a rubberized tanks is not as safe as a metal one so they installed a sensor to sniff the space between the bladder and the outer shell and throw an error code if it smells a gas leak. And overfilling the tank somehow triggered your sensor. I'm not a total expert, but this is my understanding of what's going on.

 

Don't have a GEN II but with a few other vehicles I've had, a loose or worn gas cap gave EVAP codes and engine light. Solution was change the cap and a few cycles later Bingo. When Autozone gave me the read outs they said they would sell me the expensive parts to fix, but were also the ones that said try the cap first. It worked. The o-rings or flat seals gets old too. With 183,000 miles, if the code comes back it's something to consider...and a lot cheaper. However, our resident GEN II expert might want to ring in on this.

 

Yep.