Gas filling problem, rollover valve, gas tank replacement

what did the dealer say after blowing out the vent? were there any trouble codes?

 

too much guessing. maybe have it evaluated at another dealer, or call toyota and tell them what you're going through.

 

Ask Mendel

 

I'm pretty sure if my car had that problem, I would definitely drop $15 on techinfo and review, first, the overview on how the evap system operates in the New Car Features Manual, and then any relevant Quick Technical Guides about it (under the QTG tab), and even the University of Toyota evap system course materials (under the Library tab) ... and then see if the Repair Manual had specific troubleshooting ideas for that particular problem.

I would re-read that stuff even though I've read it before. I remember that it was fascinating and, yes, it really was that complicated. As I was reading for curiosity and didn't really have an evap problem to solve at the time, a lot of it didn't stick. The time stuff really sticks is when you've got a live problem you need to apply it to....

-Chap

 

No clue. I searched my pdf of Repair Manual for:

rollover
roll over
reliever (in desperation)

No results.

I'd echo @bisco 's question: any codes?

Here's pdf of the applicable sections, maybe will help:

 

could be mechanic speak. maybe ask him exactly what he's talking about, and how he knows that that is the problem.

 

I'm guessing it means so gasoline does start coming out in event of vehicle roll-over.

 

In this thread, an owner with a 2006 had the exact same problem and reported that replacing the fuel tank filler assembly fixed the problem you're reporting.

 

The 2006 Gen 2 tank had a bladder in it. I thought the Gen 3 design did not have that.

EDIT: Never mind. I see the issue was the filler assembly, not the tank

 

Exactly. There are some pressure sensors inside the filler assembly which indicate to the pump that the tank is full.

To be honest, it seems like any pro mechanic should know this because it's probably true of every car made.

 

It appears that the US Gen 4 has some sort of valve that opens when the fuel door switch is pressed to permit refueling. If refueling takes more than 30 minutes, you need to press the switch again or have fuel spill out.

 

My Plug-in has something similar -- or maybe identical. I don't know what it does; I think it seals the tank to prevent any vapor evaporation/pollution.

 

Well, kind of ... the issue is most likely in the ORVR behavior (onboard refueling vapor recovery), and the heap of sensors, valves, and tubes making all that work is maybe the most Rube Goldbergesque system in the whole car, not to mention Toyota seems to redesign it for every Prius generation if not more often, and other late model cars probably do all have ORVR systems too, and it's anybody's guess how similarly or differently those work.

Upshot, there's probably not a pro mechanic around who knows the exact details from memory (unless your Toyota dealer is big enough to have one tech who never touches anything but your generation Prius). It's one of the few systems I know I wouldn't go near without reviewing it in the manual for the specific model year.

-Chap

 

I believe they are referring to https://techinfo.toyota.com