Help - Can't fill gas tank

[andynj]

2007 V6 100k miles no check engine light, no codes in OBD2. Last 2 times I tried to fill up at gas station pump stopped before a full tan, second time tried to force more in but filler neck filled up and overflowed on to ground.

Seems like a venting issue but need help to diagnose whether this is the charcoal canister or something else.

I put an endoscope down the neck to check for blockages and took this pic does this look normal?

Untitled by manchesterseller, on Flickr

What else should I check before ordering a charcoal canister?

 

[AuSeeker]

Are you sure the gas gauge is reading correctly?

There are known issues sometimes occurring with 4th Gens and gas gauges, not very common but it is a know issue, the issue could be with the sending unit in the tank or with the gauge itself, both are a possibility.

To try and confirm, I would fill up as much as possible and try to drive the number of miles that sorta matches up with what you think your MPG are for a tank of fuel and see what the gauge shows, when my 2004 gets down to about 1/8th of a tank or so shown on the gauge and I have driven around 310 miles, I can put in around 17 to 18 gallons, which is around 17.5 MPG for me on my daily commute, these tanks hold 23 gallons.

You might want to have a gallon or so of gas in a gas can in your vehicle just in case you run out of fuel trying to figure this out!

 

[andynj]

Are you sure the gas gauge is reading correctly?

There are known issues sometimes occurring with 4th Gens and gas gauges, not very common but it is a know issue, the issue could be with the sending unit in the tank or with the gauge itself, both are a possibility.

To try and confirm, I would fill up as much as possible and try to drive the number of miles that sorta matches up with what you think your MPG are for a tank of fuel and see what the gauge shows, when my 2004 gets down to about 1/8th of a tank or so shown on the gauge and I have driven around 310 miles, I can put in around 17 to 18 gallons, which is around 17.5 MPG for me on my daily commute, these tanks hold 23 gallons.

You might want to have a gallon or so of gas in a gas can in your vehicle just in case you run out of fuel trying to figure this out!

I don't think its my gas guage because when filling fuel backs up into the fill tube and then very slowly goes down so there is room in the tank just very slow filling. I suspect a venting issue maybe a deformed vent hose and am going to drop the spare wheel and have a poke around this weekend. I really hope its not the canister as they are $800 from the dealer.
I am hoping its not the canister as I don't have any codes.

 

[daprotege5]

most likely gas gauge is going bad, my 1st 4runner, the first couple times i would go try and fill up thinking their was an issue, the gauge showed 1/2 way gas kept going to nozzle. found this forum and of course found out gas gauge is known for going bad, replaced it and when i went to change out the gauge my tank was way fuller than the gauge was telling me, swapped out the sending unit and everything was back to normal.

 

[Buckaroo]

2007 V6 100k miles no check engine light, no codes in OBD2. Last 2 times I tried to fill up at gas station pump stopped before a full tan, second time tried to force more in but filler neck filled up and overflowed on to ground.

Seems like a venting issue but need help to diagnose whether this is the charcoal canister or something else.

I put an endoscope down the neck to check for blockages and took this pic does this look normal?

Untitled by manchesterseller, on Flickr

What else should I check before ordering a charcoal canister?

What is that blue thing in the pic? I had a problem with my third gen and it was a cap from an injector cleaner bottle that had gotten into the fuel fill hose. I cleared it by taking the hose off the tank.

 

[Parks Junkie]

I think it's unlikely the charcoal canister itself, but very well could be the overall evap plumbing.

Many years ago I had a car I had the tank out a couple of times for repairs. The evap hoses were semi hard plastic, which I damaged, and tried to seal with silicone caulk. I would fill up and the gauge would only go up to half a tank. Repeatedly. But the low fuel light would go on if I got low enough. I ignored it and ran out in a bad, bad section of SF. With much ado and a couple of miles walking I got some gas and on my way, no harm no foul, no help from SF PD driving by with me waving my arms like a madman, which I probably was and am.

I manged to plug up the evap hose, ~10-12 MM IIRC, with silicone, just trying to seal the outer hose.

If you at all trust your low fuel light, I'd carry around a gallon or 3 and see if the light comes on. If it does, you're probably low, probably for evap, but whatever. If the light doesn't come on, and I don't know how Toyota calculates this, my guess would be it's more the gauge.

 

[SocalSam]

My '03 had bad gas gauge. Luckily much easier repair than sending unit.

 

[andynj]

What is that blue thing in the pic? I had a problem with my third gen and it was a cap from an injector cleaner bottle that had gotten into the fuel fill hose. I cleared it by taking the hose off the tank.

The blue thing is the light from the camera scope I put down the fill tube best tool ever btw!

 

[andynj]

So I changed out the Charcoal canister and still can't fill the gas tank. I dont have any error codes and am starting to wonder if perhaps it is my gas gauge. Its showing 3/4 tank right now I guess I should get a container and run it dry and see what happens.

What I might do is drive 20miles or so and then try and fill, if its a gas gauge issue I should be able to pump a gallon or so of gas in. That should prove if its an EVAP issue or a gauge issue right? I'd rather not run it dry then find I have a vent issue and not be able to fill it and drive home!

How big a job is it to fix a bad gas gauge on a 2007, is a tank down deal?

 

[Ali0227]

So I changed out the Charcoal canister and still can't fill the gas tank. I dont have any error codes and am starting to wonder if perhaps it is my gas gauge. Its showing 3/4 tank right now I guess I should get a container and run it dry and see what happens.

What I might do is drive 20miles or so and then try and fill, if its a gas gauge issue I should be able to pump a gallon or so of gas in. That should prove if its an EVAP issue or a gauge issue right? I'd rather not run it dry then find I have a vent issue and not be able to fill it and drive home!

How big a job is it to fix a bad gas gauge on a 2007, is a tank down deal?

Did you ever find out what was causing the issue?

 

[Ali0227]

Are you sure the gas gauge is reading correctly?

There are known issues sometimes occurring with 4th Gens and gas gauges, not very common but it is a know issue, the issue could be with the sending unit in the tank or with the gauge itself, both are a possibility.

To try and confirm, I would fill up as much as possible and try to drive the number of miles that sorta matches up with what you think your MPG are for a tank of fuel and see what the gauge shows, when my 2004 gets down to about 1/8th of a tank or so shown on the gauge and I have driven around 310 miles, I can put in around 17 to 18 gallons, which is around 17.5 MPG for me on my daily commute, these tanks hold 23 gallons.

You might want to have a gallon or so of gas in a gas can in your vehicle just in case you run out of fuel trying to figure this out!

Are you sure the gas gauge is reading correctly?

There are known issues sometimes occurring with 4th Gens and gas gauges, not very common but it is a know issue, the issue could be with the sending unit in the tank or with the gauge itself, both are a possibility.

To try and confirm, I would fill up as much as possible and try to drive the number of miles that sorta matches up with what you think your MPG are for a tank of fuel and see what the gauge shows, when my 2004 gets down to about 1/8th of a tank or so shown on the gauge and I have driven around 310 miles, I can put in around 17 to 18 gallons, which is around 17.5 MPG for me on my daily commute, these tanks hold 23 gallons.

You might want to have a gallon or so of gas in a gas can in your vehicle just in case you run out of fuel trying to figure this out!

Curious your thoughts on similar gas gauge issue with all your experience. My gas gauge starting acting up last year. I knew the tank was full b/c I always fill up the vehicle with fuel stabil when getting ready to store it for half the year. When I took it out of storage the gauge was only reading half full and went down fast. I didn't have it hooked up to battery tender while in storage b/c there's no electrical outlet and initially thought it would work itself out but it continued. Researched online and found a thread in the other 4runner website and someone commented that it was the gas cap and it happened on two of his Toyotas and replacing the gas cap worked both times. I don't recall if he said there are vents in the cap. So for $25 I thought I'd give it a try (a lot cheaper than the sending unit) and bought a new OEM cap. The first fill didn't work (same thing happened with the gauge reading it wrong) but the next fill up worked for almost a year until it acted up again a couple of months ago. Gauge didn't read right for a couple of tanks and then gauge started working fine again.

I know it was the gauge that was off b/c I'm a little nuts and calculate the mpg's by hand every fill since I've owned her. My questions are: can it be both an issue with the gauge and the sending unit or only the gauge? Any chance trying a fuel injector cleaner could help if/when it happens again? Also, I store the vehicle half a year without the ability to charge it (no electrical outlet), could that cause issues with the gauge? Although when I took it out of storage in the spring it was fine. Thanks!