Bump...please...anyone...need some help here. What could cause the system to over pressurize or at least cause the gas to come out the vapor line and purge into the canister.

 

New theory....using a mirror and a flash light I examined the inside of both new and old tanks to follow the interior fuel lines. Found that the new tank uses all metal lines, and no rubber lines. Also found that at the end of the evap lines inside of the old tank there was a plastic yellow item suspended from the roof of the tank with a black cap with holes in it. I assume this is what draws in the vapors. In the new tank there is no such item. At least at the end of the evap line just next to the fuel pump. Instead the line just ends in the corner of the tank. All I can assume is that the vacume used to pump out the air is pumping out the air and then causing the gas to expand, to which it starts to suck out the gas into the evap lines running to the charcoal canister. IE the same princible used to siphon gas from the tank is now being worked to siphon gas fluid to my canister. Anyone else got something to add here? Advice...anyone?

 

Just uploaded two pic's to the photo gallery that show what I'm talking about. Maybe that will jog someone's memory. I've search everywhere in the Haynes manual, and I can't find it either in the Toyota manual. I called my local service department back and they said that it was the overflow fill valve. Not sure if he's right because he kept thinking I was talking about the fuel sending unit for a while. Also, can someone please double check for me the orientation of the fuel inlet pipe valve. (the nozzle that stick out of the back of your tank where your fuel goes in) On the end of it inside is a valve. I'm sure it should be hinge up as there is also a tick mark on the outter rim that should be pointing in the 11 o clock position. Does anyone know if this is right, or should it be facing another direction?

 

This can happen if the tank was overfilled. The evap sys is designed to carry vapours, so when fuel is introduced, the whole sys gets messed up. I'm guessing that the fuel was leaking out the fresh air inlet. It may take awhile for the sys to clear itself of all the excess fuel, so that it can get back to normal operation.

Always stop putting fuel in on the first auto-shutoff. Otherwise there will not be enough air space left in the tank to work properly.

 

EBAY nuff said. :disappoin

 

I have a JDM camry gen 4.5 with a charcoal canister in the engine bay. For years, I have topped up fuel to the very brim. I inspected my charcoal canister recently and found no trace of liquid fuel inside. I blew low pressure air into it and found it working well after 5 and 1/2 years. It is always hot and sunny over here, and I frequently park until the sun with full tank (to the very brim), and have never had problems with flooding of the charcoal canister. I believe there must be something wrong with your breather valve in your fuel tank. If working properly, liquid fuel should not be able to pass thru and flood the charcoal canister. Maybe the valve is missing altogether?

 

In reguards to the breather valve...is that the device I have pictured in the gallery? *last page of the gen 3 gallery

 

Ok....have an update here...

Got back in and checked out the the tank, and realized that for one, the fuel filler neck was turned about 15 degrees off so I turned it right side up again. I double checked again all the lines, except for the evap lines on top of the tank and later went and filled the tank up again. All was well, if it leaked anything , ididn't know it. About 2 weeks ago I put in more gas, but didn't top it off, still no leaks. Then this past week I topped it off once again and almost imediatly it started to just purge fuel through the fuel canister out the line that is attached to the frame (just next to the rack and Pinnion) I still have no idea what's causing this. I don't see it being the new fuel filter I installed along with the new tank, but I don't understand what in the tank is causing the problem either. I contacted a few of my local Toyota dealership and confused the heck out of one guy, and the other guy scolded me, and told me this is what I get for now having them do it. *needles to say I will never take my car to that place to have it worked on!* Anyone else having any issues with this, or have some advice for me. Might take some time this next week and put the old tank back in and see if it does it then. If it doesn't then I'll put the new tank back in and see if it starts to purge again. It only purges when the tank is first filled, and it probably purges about 2-3 or so gallons of fuel!

 

Figured I would bring this back as reading over some of the charcoal canister post recently got me thinking about this again. I haven't really thought much about this because my wife drives the car now as I have my 95 1MZ to drive. Now to sum up everything from the above posts and bring you current:
Original tank in my 93 camry I4 was leaking gas at the seem just above the exhaust pipe. I ordered a new tank for the same year off a company on ebay. Seller was a high rated seller that sold tanks and radiators. I decided to also use this chance to replace the fuel filter while I was at it. After I took out the old tank and installed the new tank I had some issues with fuel leaking still. I realized then that I had actually installed the fuel filler neck wrong so I re-installed it correctly. No more leaks from the tank. But....the very next time I filled up the tank till the pump shuts off and started up the car I noticed fuel pouring onto the ground from the engine bay. Checked it out and the bottom of the Charcoal canister was purging my gas. This went on for a few moments till I had a good amount of gas on the ground under the car. Everytime I fill the tank up the same problem happens. The tank was the same shape and size as the OEM tank, the only diference I could find was internal. Running along the top of the old tank and the new tank were metal lines. The old tank had rubber elbows for the pipes, and the new tank was all steel lines. Also I noticed there to be two canisters inside of the tank at the end of these lines, but in the new tank, these lines were not there.

So my questions to the Toyota Nation Community is this:
Any ideas on what could be causing my gas to purge? Could the fuel filter that was installed not allow enough fuel through and push it through the charcoal canister? Does anyone know what the canisters inside the tank ever are?

Images of the canister in the old tank.
http://www.toyotanation.com/photos/showphoto.php/photo/3590/cat/505
Images of new tank without canister
http://www.toyotanation.com/photos/showphoto.php/photo/3591/cat/505

please forgive the poor image quality, I was having to take the photos inside the tank very carefully so as to not drop the camera into a tank of gas!

 

I'm currently having a similar problem. I was smelling gas inside the cabin of my 98 Camry, so I took my car in to a mechanic. He said the gas was leaking from the seam of the tank, so I had the fuel tank replaced. I'm still smelling some gas inside the car and when I fill gas it overflows before the pump shuts off. Can anyone tell me what is wrong with this new tank or what is missing in the installation? Oh also, after having the new tank installed, the engine light came on which revealed code P0446 (Evaporative emissions circuit). I had this cleared and it hasn't come on now in 5 days.

Thanks...please help!

Trevor

 

In any shop where I have worked this would be called a "comeback."

That means the car has "come back" because the customer has a legitimate problem with the manner in which a repair or diagnosis was conducted. Of course, some comebacks arise from a situation where you have repalced the brakes, and the customer experiences a stallout at an intersecction, and the customer makes a causal connection between the two events. Disconnecting the battery during the brake installation could create a situation like that, particularly on cars like the Chevy Corsica, which insisted on a nice test drive to re-learn fuel trim parameters after disconnection of the battery, which causes the loss of the ECM's "keep alive" memory.

In this situation, where a fuel tank replacement has led to fuel odors inside the vehicle and an OBD II trouble code for the evap system, my first thought is a disconnected hose somewhere. The computer commands a test routine that specifically checks for evap sytem integrity using a change from atmospheric pressure in the tank and associated hoses.

Ask the service shop to look at the problem as a comeback, and give them the specific information about the fumes and the trouble code.