Cannot fill gas at a pump

[dinoman]

Hi all. Before I get into the issue, I am sorry if this post is too long. I have been having this fuel filling problem with my '07 Yaris liftback.
I can't remember exactly when it happened, but one day my Yaris started to have difficulties filling the tank at gas stations. The gas nozzle will click off when the tank is filled fast. Even if the tank is filled very very slowly, it will click off every 50 cents or so. It takes me about 10 minutes to get $10 worth of gas. Finally I got too annoyed with the issue as in New Jersey we cannot pump our own gas due to state law (attendant will walk away and sometimes won't continue to pump my gas for very long time)

Initially I tried to fill at different stations thinking it may be due to some particular pumps, but I have the same issue at all gas stations. I have googled some possible causes and decided to investigate if my evap/charcoal canister is blocked. Since my car also had rough idle when stopping, I figured that the canister is faulty and also not alllowing fuel vapor to pass to the purge valve. I checked this by blowing air into the canister and the air did not freely blow out of the other 2 openings. Strangely, there was no check engine light (CEL) on even with this potential canister issue. I replaced the canister and the rough idling seems to have been fixed, but I am still having issues at the pump. Still the CEL is NOT on.

Thinking it may be the vent hose blockage, I disconnected the vent line hose from the canister filter (a smaller black container near the charcoal canister) and tried to fill the tank. The nozzle still clicks off and could not be filled easily. I also took off the air inlet line hose (i believe this connects the fuel tank and the canister) and tried to see if the blockage is somehow still at the canister. The nozzle stilll clicks off often and could not refuel easily. Does this mean the blockage is at the actual filler neck? Is there any other mechanism that controls the air venting to the canister?

I am sort of lost what could be the issue and will greatly appreciate any advices and inputs. One attendant at the pump has mentioned to me that he could swear that other Yaris had a metal "flap" at the fuel filler door where the pump nozzle goes in. Since in New Jersey I am not allowed to pump the gas myself, I actually do not know if there is supposed to be a metal flap. I would appreciate if anyone can check if their Yaris has a metal flap that covers the hole where the gas nozzle goes in.

Again, sorry for the long post.

[razingman]

just take it to a mech, means the hose is blocked an they can snake it or put special oil in it

[dinoman]

razingman, thanks for your input. While I do believe it is possible that there is something blocking the fuel filler neck, I am hoping to find out whether there is something I missed before I take it to a mechanic.

I found the answer to the "metal flap" here on Yarisworld. Apparently the Yaris does not have these.

http://www.yarisworld.com/forums/showthread.php?t=31250&highlight=fuel+filler

If the fuel filler neck is not blocked, what else could cause this problem??? Any help is appreciated!

[jambo101]

You probably have a blockage in the gas filler vent line as when you are filling the tank the air being displaced in the tank has to go somewhere,that somewhere is the smaller pipe on this Camry filler neck.. Might need nothing more than a shot of compressed air to evacuate what ever is in the pipe

http://static.1aautoimages.com/partimage/FMX/1AFMX00027/main.JPG

[dinoman]

thank you for your input. If I am correct, if any of the vent lines were blocked, taking off the air vent hose which connects the tank and the canister should have helped with the problem as this bypasses all vent lines? When I took this off and tried to fill up at the pump, the pump nozzle kept clicking off still, which led me to believe that there is something mysterious going on here.

I tried to summarize what I did in the diagram below so people can follow me easier. The canister assembly, which includes the vent valve and the canister pump, has been replaced with a new one. From my troubleshooting steps, it appears that the problem may be somewhere between the canister and the pump nozzle entrance. Does this leaves me with only fuel filler neck as the possible place of blockage? I am not sure what mechanism controls venting of the fuel vapor through the fuel pump assembly inside the tank, but I believe the blockage there is not likely to occur?

[dinoman]

Does anyone know what the second vent line that goes directly from the tank back to the filler neck do? In the Yaris factory service manual under the "FUEL" section, it is called fuel tank breather hose (page FU-42) and seems to be different from the vent line from the canister. When I was checking under the car, I did notice this line but figured that its too skinny to let large volume of air through while filling the tank. I believe the hole for this breather attached to the filler neck much deeper than the vent hose from the canister.

[Lux]

jambo101 has already addressed that question. The vent is for displaced air when filling the tank.

There are only three exits from the tank when refueling: the EVAP line, the filler vent, and the filler neck itself. The EVAP system is an ECU-controlled valve and it is always closed when refueling. If the filler vent is blocked, the in-tank air will force itself back up the filler neck when attempting to refuel, thereby activating the pump's trigger stop.

[dinoman]

Lux, thank you for your post. So are you saying that the EVAP system does not vent air through the canister when refueling? Please correct me if I am wrong, but I thought that the EVAP vent valve was open during refueling. My understanding was that the vapor from the tank that is displaced during refuel is pushed through the EVAP system and "cleaned" before going back to the atmosphere. As you mentioned, the canister has a ECU controlled valve that opens or closes depending on fueling or driving. When the car is driving, the refuel vent valve is closed to allow the vapor to be directed towards the purge valve to be burned as fuel. During refueling, the vent valve is open to allow the vapor to pass through the canister to be cleaned before leaving the system. If you look at the schematic on my 2nd post, the vapor during refuel is pushed through the EVAP system (arrows showing the direction of the vapor travel). This diagram was copied directly from 1NZ-FE manual I found here (http://www.autoclub72.ru/forum/index.php?act=attach&type=post&id=1552). Do you mean that this tube that goes directly back to the filler neck is the real filler vent and not the EVAP system vent as shown in the diagram?

I checked all the lines for the EVAP system using a compressed air can as Jambo101 has suggested and found that air flows through all the lines properly. I'll try to check the line that goes directly back to the filler neck tomorrow.

[jambo101]

A few other maybe's
http://community.cartalk.com/discussion/533010/slow-fill-gas-tank

[Billiam]

Try pulling the nozzle out a bit when you fill up. This can help.

[dinoman]

thanks for that suggestion. Actually attendants usually try pulling the nozzle out, flipping the nozzle upside down, and all other types of tricks that they say work. The gas still doesnt go in without clicking off. I found some wire hangers, so Ill try and see if I can check if there is something blocking the filler neck. I also need to check if that vent line that goes directly back to the filler neck is blocked and is causing the problem.

Since we were talking about ECU-controlled valve earlier, how do I know if the ECU is working properly? I thought the idle problem was fixed, but this morning on my way to work I noticed that the RPM still drops a little too much when I come to a stop. It may be because I disconnected the battery to clear the CEL codes and the ECU still trying to learn the right fuel-air mixture? The purge valve seems to be okay when I took it off and checked it by applying voltage.

[nookandcrannycar]

thanks for that suggestion. Actually attendants usually try pulling the nozzle out, flipping the nozzle upside down, and all other types of tricks that they say work. The gas still doesnt go in without clicking off. I found some wire hangers, so Ill try and see if I can check if there is something blocking the filler neck. I also need to check if that vent line that goes directly back to the filler neck is blocked and is causing the problem.

Since we were talking about ECU-controlled valve earlier, how do I know if the ECU is working properly? I thought the idle problem was fixed, but this morning on my way to work I noticed that the RPM still drops a little too much when I come to a stop. It may be because I disconnected the battery to clear the CEL codes and the ECU still trying to learn the right fuel-air mixture? The purge valve seems to be okay when I took it off and checked it by applying voltage.

I'm quite fond of New Jersey and Oregon, but that nanny state 'not allowed to pump your own gas' law in both states drives me nuts....both because of how it effects me and the reasoning behind it. In New Jersey I try to get gas late at night and pick a large station plus the pump that is the most hidden from the attendant. I then start pumping the gas myself and if the attendant comes over I plead ignorance and the attendant sees my non NJ-NY-CT plates and explains the law to me. I always fill my tank to the top to get a consistent reading re how I'm measuring MPG. If I'm in Bergen County and am going to be going to Nyack that day, I can't bring myself to get gas in Nyack and pump it myself without issue because I don't want to pay the higher gas prices in New York State. If I'm in CT or NY and need gas (and will be driving back to Texas) I'll put in just enough gas to get to PA and then fill up in PA.

[dinoman]

Sorry I have been busy with work and little time to work on this problem.
I checked all the vent lines and there seems to be no blockage anywhere. I even disconnected the fuel tank vent hose (the skinny tube along the filler neck) and it was also clear when I shot can of compressed air through it. I even pushed solvent-resistant tubing into vent lines and the tube came out of the filler end without much effort.

I tried again to troubleshoot while filling gas at the station. I removed the line that connects the tank and the charcoal canister. No good. I disconnected the skinny vapor breather line and while I did hear some vapor/pressure being released, the gas still continued to click off. This was strange because earlier when I tested the vent line with compressed air, a lot of air came through. Not sure why there was some pressure built up in the line. Either way. removing the vent line didnt let the gas go into the tank easily, so the blockage could be somewhere else? Or does everyone think it is still the vent hose due to the released pressure?

I read that cars come with "rollover valve" that is at the tank end of the filler neck. I am assuming the Yaris has this also for safety. When I push the tubing into the filler, I can hear what seems like a spring-loaded flap open and close. There is really no resistance at all, just the sound that seems like a flap pushed open and closed when I remove the tube. I feel that if there is a flap at the tank end, it should stay open to allow fueling. Does anyone know anything about this? Is the flap serviceable or tank replacement the only option in this case?

I am very close to taking it to a mechanic as I am completely lost.

[dinoman]

I took the car to the dealership here in Cherry Hill, NJ, to have the problem diagnosed today. The fueling problem could not be diagnosed even by their service technician. They said they contacted Toyota Tech Support and was advised to replace the fuel pump and the fuel tank. I was told that these may or may not fix the problem as they need to re-evaluate the problem once they replace these (quoted $1150). They pretty much reached the same conclusion I did from my own troubleshooting above. :iono:

They did confirm that there is a rollover flap for safety inside the tank where the filler neck meets the tank. Their advice to change the tank is based on the possibility that this flap may not be functioning properly. Again, they are not sure. The tank is $480 and its not something I would like to change based on just assumption.

Personally, I would put my money on the fuel pump. They said the vent valve on top of the fuel pump assembly is sticking. This is noted on the copy of the workorder I received. Now, I am not sure if there is actually a mechanical valve on top of the fuel pump but this could be the problem as I never felt vapor coming out of the connection that goes to the canister. For this, I was told to replace the plate assembly, regulator assembly, and couple of other parts which comes out to ~$300 for parts. I think it is wiser to just find a good used fuel pump and replace the whole thing and save myself some time and trouble.

I did some quick searches for a used pump but I would like to ask few questions to anyone with the knowledge about the fuel pump for Yaris.
Are the same fuel pumps used on the hatchback and the sedan? Also there seems to be different pumps depending on the year of the car. I have a 07 hatchback but can I still use fuel pumps from a newer Yaris (e.g. pumps for 09-11 models?) Finally, do I need a special tool to remove the retainer off fuel pump to remove it from the tank?

I never serviced a fuel tank, so any advice on precautions I should take is also greatly appreciated! I would like to do this safely. :laugh:

[CoryM]

The fuel pump has nothing to do with getting gas into the tank. The only thing that has to happen is the air in the tank needs to be able to travel up the filler vent hose (red in picture), and out to atmosphere. Fuel goes in, air comes out. Otherwise you create pressure and it trips the shut-off. The only other possible cause is that the fuel filler tube is blocked.

If it were mine, I would remove the fuel filler hose assy which includes the vent hose. Inspect for any blockages and correct if any are found. If nothing visible there you will have to drain tank, remove the pump from the tank and inspect the filler vent hose tube on the tank. There is no reason to replace fuel pump, and likely not the fuel tank. Probably just a chunk of foreign material in the filler neck/vent.

Step one: remove filler neck and inspect filler tube and filler vent tube.

[CTScott]

The fuel pump has nothing to do with getting gas into the tank. The only thing that has to happen is the air in the tank needs to be able to travel up the filler vent hose (red in picture), and out to atmosphere. Fuel goes in, air comes out. Otherwise you create pressure and it trips the shut-off. The only other possible cause is that the fuel filler tube is blocked.

If it were mine, I would remove the fuel filler hose assy which includes the vent hose. Inspect for any blockages and correct if any are found. If nothing visible there you will have to drain tank, remove the pump from the tank and inspect the filler vent hose tube on the tank. There is no reason to replace fuel pump, and likely not the fuel tank. Probably just a chunk of foreign material in the filler neck/vent.

Step one: remove filler neck and inspect filler tube and filler vent tube.

You can easily remove the filler hose from the tank, to check it out, without removing the tank. When I have dropped the tank, I first remove the filler hose and siphon as much out from there as possible before removing the tank.

[Jason@SportsCar]

How many miles on your car? Even though it is a 2007 it may still be within the Fed emissions warranty - and many fuel related issues like this fall into that category.

[dinoman]

thanks for all the suggestions.

i got about 150K miles on my car now. my commute is pretty long. Im sure all warranties are expired...

If i have some time this weekend, ill try to look at the filler neck as suggested.
I tried to look for a procedure to remove the filler neck, but I could not find it listed in the [Fuel] or [Emission Control] section of the service manual. Does anyone have the procedure to get the filler neck off? Don't want to break something in the process and be out of car to drive.

[CTScott]

It is kind of strange that the service manual doesn't seem to have a section that shows how to work with the fuel filler. It just shows the removal of the hose clamp from where the flexible portion of the filler pipe meets the tank.

If you remove the rear left wheel you will see a plastic cover which protects the filler pipe assembly (pictured below). The cover has three clips that hold it to the wheel well. Once your remove it you have full access to remove the filler assembly.

48059

48058

[dinoman]

I hope I am not speaking too soon, but today I went to fill up for the first time after taking this car to the dealer. The car was able to take gas now without the nozzle clicking off. I asked the attendant to go slowly out of habit, so it may still click off if they went full force. Before it will not take gas no matter how slow it pumped. Next time I will have them go full flow and see if it will click off.

Now, I am writing this in case someone has similar problem as me. This way they can try to diagnose the problem as I was able to talk with the technician who diagnosed my vehicle. He was very patient and took time to explain things to me clearly. He agreed that there are 3 lines out of the tank: the filler neck, the skinny hose along the neck, and the valve on top of the pump. He told me that he removed the filler neck off the car and checked for anything unusual, but didnt even find a bit of residue buildup. He also mentioned that the rubber hose that attaches to the tank was clear. He said they were both very clean.:thumbup: He also told me that the skinny vent line attached to the filler neck was clear but blew the thing with 140psi pressure. The technician went to fill up the gas afterwards and noted the gas nozzle still kicks off. He said the first 2 lines out of the tank were definitely not the problem.

He then proceeded to remove the fuel pump assembly from the tank and while doing so, he saw the rollover flap in the tank was bent and not closing properly. He said that may not matter for the fill up, but he said that was the first unusal thing he saw. Toyota technical support advised him that the tank needs to be replaced. If it was stuck in the closed position, I would agree with the tech support that this may be part of the problem. There is a vent valve on top of the fuel pump. He explained to me that it has a spring loaded valve that opens and closes depending on the pressure from the tank. I have never seen the tank except for the pictures on the internet or in the service manual so I cant comment on this. He said only tiny amount of air would make it through the valve when he tried to blow some air through it. That was the second abnormal thing he noted about my fuel system. He told me he took the fuel pump top plate apart and checked for anything obvious. Maybe him taking apart the valve dislodged something he missed i am not sure.

Now, I don't know what is correct, but he told me that the skinny hose along the fuel filler neck is not for venting the tank. The valve on top of the fuel pump lets the vapor out through the canister and into the atmosphere. I know wiki is not a good place to find answers but it basically supports what he told me.
http://en.wikipedia.org/wiki/Onboard_refueling_vapor_recovery

He said the purpose of the skinny hole is to tell the gas pump when the tank gets full. I am not sure if i understood him correctly, but that skinny hose submerges in the gas and then gets blocked to create vacuum at the nozzle. Not really sure how that works, but having this tube blocked with spiderweb or anything is likely to mimic your tank being full.

So in future if anyone experiences strange problem like me, you can try and check that vent on top of the fuel pump.

[dinoman]

CTScott, thank you for the procedure to remove the filler neck. Hopefully the gas problem is gone now and I don't have to take the filler neck off the car... The informatin will probably come in handy one day...

[CTScott]

That definitely makes sense. That hose goes to the refueling valve on the canister assembly.

[CoryM]

From an environmental pov, the idea is to reduce the amount of fumes getting let out. So this is why we have charcoal canisters etc instead of just venting the tank to atmosphere. Then you go and open the fuel cap and spray agitated fuel in (releasing lots of fumes). This is not what they want. So, they create a system to suck in the fumes while you fuel up.

I would have to look at exactly how it is routed or see the diagram for the Yaris to say for sure, but I am assuming the 16mm(?) hose goes from the top of the filler neck to the top of the tank. Can anyone confirm this? I've not looked at the Yaris yet.
If so, this is the one and only vent hose you need in order to let the air out while refuelling.

Here's hoping your car is working fine now :iono: If you drive like me it will be a month before you find out though :laugh:
Cheers.

PS: the reason the gas station pump shuts off is because there is a small hose inside the gas station pump nozzle. When this hose gets blocked with fuel, the pump shuts off. Nothing to do with the car.

[Fidelio]

I have this exact same problem. I have the check Engine light and i get p0441 code. I will start off with checking the top of the fuel pump. I wonder if every 2007 HB has this problem.

LOL At first I thought someone was smuggling contraband in the tank. I bought this car used on Craigslist.

[RedStickHam]

My wife had this same problem on her Hyundai Accent. It was a combination of the cannister and the pump used to vent emissions vapors. She had to replace both items and it wasn't cheap, plus they had to order the parts. The one thing different in her case was the check engine light was on.

She saved money by taking it to a good independent repair shop as opposed to a dealer, but they still charged a lot of money.


RedStickham

[Fidelio]

I found the charcoal canister today on a car that was totaled at 9K miles. They have the fuel pump as well. I think Ill replace that too.

Does the tank on the HB have to be dropped? Or it accessible by removing the back seat?

[Fidelio]

The charcoal canister fixed the problem. I didnt need to replace the pump since it was already working.

[CTScott]

The charcoal canister fixed the problem. I didnt need to replace the pump since it was already working.

That makes sense, as the fuel pump has nothing to do with the evaporative emissions system. For future reference though, you can get to the fuel pump without dropping the tank. You have to remove the rear seat, and then there is an access panel to the top of the tank. A special spanner tool is required to easily remove the screwed on tank cover.

[Fidelio]

I am getting a p0441 now. I just replaced the gas cap so hopefully it will clear, if not its either a vacuum leak or purge valve. Man if it isnt one thing its another with these fuel emission system.

My Corolla ran forever without ever needing anything. I need to fix this problem since it has to be smog checked.

[CTScott]

I am getting a p0441 now. I just replaced the gas cap so hopefully it will clear, if not its either a vacuum leak or purge valve. Man if it isnt one thing its another with these fuel emission system.

My Corolla ran forever without ever needing anything. I need to fix this problem since it has to be smog checked.

Hopefully the gas cap does it. The biggest hassle is that it requires the six hour powered off after a drive to run the evaporative system test.

[Fidelio]

The last thing I did yesterday after parking it in the garage was unplug the battery and the EVAP hoses then sprayed compressed air through the lines. Next I used a small amount of wd40 and sprayed compressed air inside the Purge VSV with the hoses being unplugged and allowed some minor gunk to land on a rag towel.

I let it sit over night. Today I plugged the battery back on and the check engine turned off on the first start, so I suspect that it was the Gas cap and with a dirty purge VSV.

I am sure this thread will be useful for someone running into the same problem with subcompact cars.

http://i1051.photobucket.com/albums/s427/MOTOGENICS/DSCN0277_zpsad897e65.jpg

[chaditotx]

Man.... all this reminds me of issues I had with my wifes 2001 camry. She had a tendency to "top off" her tank with the old click .... click.... click... at the pump. It began to slowly saturate the carbon canister and related on the old camry with fumes etc, and ate most of the vacumn check valve diaphrams up. No replacement check valves avail, just a $500 canister. uggh. Worked great until a year later, and couldn't fill the tank as you described. Found "mud dobbers" had started to build a nest in the vent hose. Cleaned them out and put stainless screen over it. Gotta love bugs in Texas.

I guess just trying to pass on to everyone don't top off with the click .... click.... thing.

[John Henke]

My wife has a 2007 Yaris. A few days ago I was going to fill it with gas to discover I needed and eye dropper to put in the gas because the filler neck kept filling up with gas and shutting off the pump. Well today I fixed it. Here’s the problem, what causes it and how to correct it.
The think vent on top of the gas tank has a rollover valve. If the car ends up on its top this valve has a weight that will shove a piston into the vent closing it off. These vents are designed to stay closed even after the car is righted. When the valve is closed the air in the tank can’t vent to the carbon canister when the gas is being pumped in.
The way I think it gets closed without being inverted is because a Yaris is such a bump-mobile being as light as it is I think inertia drives this weight into the valve when hitting bumps in the road. Maybe a little at a time the vent just gets closed off, or a really big bump will do it maybe. This car has over 60,000 miles.
Here’s the fix. Detach the vent hose at the carbon canister; it’s the one toward the front of the car. Take off the gas cap. Use an air compressor to pump air pressure into the vent line; you’ll have to make up some kind of stopper to make the connection fairly air tight. Apply 15 or 20 PSI to the line for about 30 seconds. Pull out the connection and it should expel some of the air and gas fumes. (No smoking during this procedure.) You should be able to blow air into the tank and suck it out just with a hose in you mouth. In fact the hose in the mouth is a good way to confirm that the vent is closed.
This is what I did today after thinking over the situation for a couple days and reading the posts here and looking at the schematics. I went to the gas station and locked the handle on full and it just filled right up. Good luck, don’t buy parts, you can do this yourself.
John Henke.

[John Henke]

Yesterday I went through all of the rig a ma roll to get registered in this sight to tell you folks what causes this and how to correct it but I still don’t see my post anywhere. It’s literally a 15 minute fix and no parts are needed and no money has to be spent. But ho well. Good luck!

[John Henke]

Too bad I don’t feel like telling the story again. Maybe later.

[tmontague]

I had this issue on my 02Hyundai Accent before I got my Yaris. Caused by filling tank "topping up" after the nozzle clicks off. This caused charcoal to move out of canister and into one of the black rubber hoses just beside the canister . I would have to reach under car just under the fuel door and remove one end of the hose and let a bunch of charcoal pellets fall onto the ground. I'd do this when I'd squeeze the hose and it would feel crunchy meaning it was full if charcoal. It beat buying a new canister.

Not sure if this helps at all with the Yaris bit I figured it can't hurt.

[bronsin]

Thanks John! :bow:

[tdutzi]

I had a similar problem on my wifes 2000 toyota echo. Her filler neck was badly rusted. I replaced the filler neck and had to clean rust chips out of the intake pipe to the tank. The tank intake pipe has a screen at the end which trapped the rust chips that fell down the filler pipe and went through the rubber hose to the tank. Now the car fills up like new!

[Flipper_1938]

My wife has a 2007 Yaris. A few days ago I was going to fill it with gas to discover I needed and eye dropper to put in the gas because the filler neck kept filling up with gas and shutting off the pump. Well today I fixed it. Here’s the problem, what causes it and how to correct it.
The think vent on top of the gas tank has a rollover valve. If the car ends up on its top this valve has a weight that will shove a piston into the vent closing it off. These vents are designed to stay closed even after the car is righted. When the valve is closed the air in the tank can’t vent to the carbon canister when the gas is being pumped in.
The way I think it gets closed without being inverted is because a Yaris is such a bump-mobile being as light as it is I think inertia drives this weight into the valve when hitting bumps in the road. Maybe a little at a time the vent just gets closed off, or a really big bump will do it maybe. This car has over 60,000 miles.
Here’s the fix. Detach the vent hose at the carbon canister; it’s the one toward the front of the car. Take off the gas cap. Use an air compressor to pump air pressure into the vent line; you’ll have to make up some kind of stopper to make the connection fairly air tight. Apply 15 or 20 PSI to the line for about 30 seconds. Pull out the connection and it should expel some of the air and gas fumes. (No smoking during this procedure.) You should be able to blow air into the tank and suck it out just with a hose in you mouth. In fact the hose in the mouth is a good way to confirm that the vent is closed.
This is what I did today after thinking over the situation for a couple days and reading the posts here and looking at the schematics. I went to the gas station and locked the handle on full and it just filled right up. Good luck, don’t buy parts, you can do this yourself.
John Henke.

You probably blew the guts out of the ROV with that sort of air pressure/volume. Time for a new gas tank.