Gas tank building excessive pressure & fuel smell. Dangerous for sure! Why does this happen? (1 Viewer)

[nissanh]

Not sure the how the gasoline is heated on the LC. I had a boiling gasoline in my corolla back in summer of 2011 when I drove from Vegas NV to King man in AZ. The issue later found out was a metallic coolant line is used to heat the return gasoline line. Once I bypass the coolant line, I never experienced boiling gasoline in the tank.

There is a vent tube on the charcoal canister running towards the bottom of the battery tray, see the solenoid is working there.

 

[s2kutah]

Following: 2004 LX470, loaded with family camping gear and going into the Utah Mountains, it happens all the time. Looking forward to hearing more. Makes sense that it's getting hot with going slow and the pressure building with elevation.

 

[Jfoofighter16]

Following: 2004 LX470, loaded with family camping gear and going into the Utah Mountains, it happens all the time. Looking forward to hearing more. Makes sense that it's getting hot with going slow and the pressure building with elevation.

Agree at altitude when on trails/wheeling/going slow it accelerates the problem but I am having this after running highways on hot days too. Drove to/back from c springs/denver (about 2.5 hours round trip) and had I driven another hour or hit any stop/go traffic I would have had boiling fuel, I got home just as the pressure started making fumes/smell out of gas cap but the gas wasnt bubbling/making boiling sounds just quite yet. I had no traffic and was driving 60-70 for most of trip and obviously no high mtn pass altitudes with that drive. It was quite hot/warm for our area though (temps reading high 80s to 90s in car)

 

[VagabondJesse]

I don't have a whole to add past a "yeah, me too", but it happened to me again on Saturday. I was on a trail near Glenwood Springs, CO which started at around 7k feet. I noticed the fuel smell when I got out to relieve pressure in a different kind of tank. I'm just used to it now and don't think much of it. Later, I got stuck High-centered on a snow drift at 10,300'. The truck was leaning pretty heavily to the passenger side. I got out to put a recovery track under my driver's side rear tire and noticed fuel was just pouring down from somewhere around the filler neck. Nothing was dripping down the exterior, but I think it may be possible that it came out the cap and found a path to the underbody because of the rather extreme angle we were at.

However, being high-centered on a snow drift must have had the benefit of cooling the fuel tank down (also, the truck was idling during most of recovery which helped too, I'm sure) because by the time I got un-stuck, there was no more fuel spilling out. In fact, I don't remember even smelling fuel at that point, but that wasn't my main focus, so I can't promise.

I'll probably try the homemade heat-shield fix in the coming weeks to see if that makes a difference. Will report back.

 

[gatormark91]

Check for exhaust leaks. That was my problem, it was heating up the fuel tank.

 

[Jfoofighter16]

Check for exhaust leaks. That was my problem, it was heating up the fuel tank.

Can you elaborate how you did this...this is my second hunch for why/where the problem is. I have had repair shops/dealer say "we checked, its fine" but their version of thorough checking is likely not what I would do if I knew how to best tell myself. Wpuld a pyrometer work and look for sections of exhaust running super hot (if so what temp is "too hot") any tips/tricks here would help. Anytime I bring to a shop they invariably let it sit and then say "we couldnt get it to heat up like you are seeing" and obviously hard to get it to a shop when on a trail in middle of nowhere when problem pops up!

Thanks!

 

[saucebox]

Check for exhaust leaks. That was my problem, it was heating up the fuel tank.

Finally, a justification for a Borla.

Kidding...kind of. Won't fit with the skid plates.

 

[Jfoofighter16]

Finally, a justification for a Borla.

Kidding...kind of. Won't fit with the skid plates.

Haha may want to check with use J1000...he mentioned borlaug exhaust when discussing this issue with him on separate thread/convo that's out there....only problem on his end is I believe he has gotten borlaug and rest of exhaust checked and still has this problem too. But that seems to be how it goes on this one, several failure points/places where ppl have fixed one thing and problem goes away whereas other fix same thing (i.e. gas cap, canister, etc) and still have the issue. At this pint I've damn near redone my fuel system minus the lines themselves and done most of evap system too, so I'm left with cooling systems (which all appear to be fine) or exhaust (which I've only done passenger side catalytic converter so far) so for me at least it's exhaust or something fuel pressure regulator and/or fuel injector related. But at this point who knows. I cant just replace entire car with OEM parts at a certain point, so I may part with this thing without ever solving despite my stubbornness in thinking theres a way to get this fixed.....at the end of the day it may just be something where some of these cruisers are just going to do this at their age, but then I read about brand new 200s doing this or others bought their 100 new and had this problem from day 1 so IDK!!

 

[saucebox]

Haha may want to check with use J1000...he mentioned borlaug exhaust when discussing this issue with him on separate thread/convo that's out there....only problem on his end is I believe he has gotten borlaug and rest of exhaust checked and still has this problem too. But that seems to be how it goes on this one, several failure points/places where ppl have fixed one thing and problem goes away whereas other fix same thing (i.e. gas cap, canister, etc) and still have the issue. At this pint I've damn near redone my fuel system minus the lines themselves and done most of evap system too, so I'm left with cooling systems (which all appear to be fine) or exhaust (which I've only done passenger side catalytic converter so far) so for me at least it's exhaust or something fuel pressure regulator and/or fuel injector related. But at this point who knows. I cant just replace entire car with OEM parts at a certain point, so I may part with this thing without ever solving despite my stubbornness in thinking theres a way to get this fixed.....at the end of the day it may just be something where some of these cruisers are just going to do this at their age, but then I read about brand new 200s doing this or others bought their 100 new and had this problem from day 1 so IDK!!

Me neither. Doesn't seem to help we both live where elevation is easy to attain. Bootyfab heat shields are next for me, but I'm not sure when I'll get to it before the end of July. At the advice of one of the other threads, I also bought some kind of gas tank valve thing at the recommend in the other thread, but have yet to install it. Every time I think of it, I've just filled the tank.

 

[Jfoofighter16]

Me neither. Doesn't seem to help we both live where elevation is easy to attain. Bootyfab heat shields are next for me, but I'm not sure when I'll get to it before the end of July. At the advice of one of the other threads, I also bought some kind of gas tank valve thing at the recommend in the other thread, but have yet to install it. Every time I think of it, I've just filled the tank.

Have not heard of gas tank valve you refer to...have any more details?

 

[saucebox]

Have not heard of gas tank valve you refer to...have any more details?

Oh man. I'll have to see if I can locate it again. It was relatively cheap as far as parts go. I'll update if I can put my hands on it this afternoon. Have to run for a bit.

 

[riffman12]

I had this happen in my 80 series once. The 80 guys all replace the factory charcoal canister with an OEM unit or a cheaper AC Delco unit that looks similar enough. It seemed to fix mine, but there were plenty of high altitude guys who still had issues after the replacement.

I've never had this happen on my LX yet, but have not been higher than ~10k feet yet.

It's really frustrating and I find it bizarre that this is happening for a vehicle built from the ground up to get through any conditions. Especially that it's an issue through two totally different generations of vehicle.

I can't imagine it's just an exhaust heat issue. Toyota must have thought of that. The system is designed to vent pressure (I assume under pretty much any condition) so it's either overwhelming the system or something is stuck closed.

The other thing I have heard mentioned is that it is due to ethanol in the fuel, which was not around when the 80 series was new. I would have thought Mr T would think of that on the 100 though.

That's terrifying to hear that there is liquid fuel pouring out of a running vehicle. I'm amazed Toyota didn't step in after that guy had his 100 burn to the ground in Alabama Hills.

 

[Jfoofighter16]

I had this happen in my 80 series once. The 80 guys all replace the factory charcoal canister with an OEM unit or a cheaper AC Delco unit that looks similar enough. It seemed to fix mine, but there were plenty of high altitude guys who still had issues after the replacement.

I've never had this happen on my LX yet, but have not been higher than ~10k feet yet.

It's really frustrating and I find it bizarre that this is happening for a vehicle built from the ground up to get through any conditions. Especially that it's an issue through two totally different generations of vehicle.

I can't imagine it's just an exhaust heat issue. Toyota must have thought of that. The system is designed to vent pressure (I assume under pretty much any condition) so it's either overwhelming the system or something is stuck closed.

The other thing I have heard mentioned is that it is due to ethanol in the fuel, which was not around when the 80 series was new. I would have thought Mr T would think of that on the 100 though.

That's terrifying to hear that there is liquid fuel pouring out of a running vehicle. I'm amazed Toyota didn't step in after that guy had his 100 burn to the ground in Alabama Hills.

I thi k they are going to argue we had modded and/or arent using vehicles for their intended "mall crawling purposes " by taking it off road by the time we get to 100 series LOL! seriously though I wish there was some guidance/acknowledgement from Toyota on this....not sure if this is true or not but I saw on a thread that at a HIH one year they got a toyo engineer in their to speak and he got grilled on the tank venting and this dude's response was "let the system do it's thing" essentially....which isn't reassuring that Mr. T is apparently saying "just let it vent explosive fumes in an uncontrolled environment, it's just doing its thing" !!!! I wasnt there obviously so not sure how true this is.

 

[87warrior]

Have not heard of gas tank valve you refer to...have any more details?

This is the only valve on the fuel tank I am aware of:

 

[saucebox]

This is the only valve on the fuel tank I am aware of:

Thank you, that's the one.

 

[T3QCruiser]

Same issue here with my 1998 LC. I live in a warm weather climate and have driven it for 3 years here and never noticed any fuel smell or abnormal fuel tank pressure. The gas cap does vent pressure when opened when warm but only a second or two. Went wheeling this weekend and noticed A LOT of fuel smell so I decided to crack the filler cap and vapors were escaping vigorously for as long as I would dare to keep it vented which was several minutes until I no longer felt comfortable keeping it open.

What I want to add here is I have a STANT 10825 aftermarket fuel filler cap (that's been on there since previous owner). I made a separate thread asking about the difference between OEM fuel filler caps (link below) but I do wonder what the cap contributes to this issue. Seems like there are a host of smaller issues that work in conjunction to create this larger issue. It also seems like one or several of the smaller issues can cause the fuel tank pressure problem so there may not be one universal fix.

My STANT cap was in pieces when I came home from my wheeling trip when I checked it the next morning. The spring, spring retainer and metal disk was sitting atop my fuel filler flap. I was able to re-assemble it for now while I figure out which cap to buy.

If anyone has thoughts on fuel filler cap differences, I'd like your feedback here:

100 Series Fuel Filler Cap Differences?

I've owned my 1998 2UZ Land Cruiser for 3 years and it's had a Stant 10825 aftermarket fuel filler cap presumably for many, many years from the previous owner. I've read about all the fuel pressure issues people have had and was pleased I never had them...until this week as the weather has been...

forum.ih8mud.com

 

[riffman12]

If it were my car I would only buy an OEM fuel cap

 

[T3QCruiser]

If it were my car I would only buy an OEM fuel cap

Not sure if this is in response to my post above but I agree, I want an OEM fuel cap, especially after seeing the STANT cap that was installed by the previous owner come apart. My question was more oriented toward WHICH OEM cap to get, the untethered part called for in the 98-99 years or the 2000+ version with the tether. I'm trying to determine if there are differences besides the tether as my preference would be to get the tether for convenience.

 

[95Fantasma80]

Not sure if this is in response to my post above but I agree, I want an OEM fuel cap, especially after seeing the STANT cap that was installed by the previous owner come apart. My question was more oriented toward WHICH OEM cap to get, the untethered part called for in the 98-99 years or the 2000+ version with the tether. I'm trying to determine if there are differences besides the tether as my preference would be to get the tether for convenience.

honestly the tether is annoying, all i need is a place to rest gas cap when unscrewed I'm not dropping it or losing it... I'm not a toddler lol

I undid tether and don't use it.

good question though, i wonder if any changes.

 

[T3QCruiser]

honestly the tether is annoying, all i need is a place to rest gas cap when unscrewed I'm not dropping it or losing it... I'm not a toddler lol

I undid tether and don't use it.

good question though, i wonder if any changes.

Price is the same for either and tether feels like cheap insurance when wife drives.