I do have a shiny new Borla exhaust on my truck. I notice boiling starts at 115*F on my fuel temp sensor.
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100 Caught fire & gas tank venting concerns
- Thread starter Skidoo
- Start date
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Ugh, well at least I know to not just go running and blindly replacing exhaust components, haha...I will have to see if I can pick up fuel temp on my obd2 scanner/app. At least if I see myself getting up there in temp I can try to pull over and let the rig get a break.
Good idea. I have the BlueDriver OBD2 reader and app for my 2006. I don’t remember seeing a fuel temp live data item but will need to check.
Wait....we can pick up fuel temps? Is there a code for that on my ScangaugeII? That would be fantastic to know
2001LC
SILVER Star
Fuel temp??
Could this be exhaust gas temp?
Could this be exhaust gas temp?
If I remember correctly @J1000 has an E85 conversion on his 100 and has a few other monitoring devices installed so fuel temperature is a possibility.
guardcompany
Shea
I'm still chasing this as well... So far I've done:
- Gas cap (didn't work last summer)
- Muffler (haven't test yet)
- Wrapped fuel lined with heat shielding (haven't test yet)
- 2 pre cat o2 sensors (haven't test yet)
Next up this weekend:
- Fuel pump
- Building heat shield
Then I'll order the CC, VSV and hoses:
I've been dealing with this issue over the years and I really believe its a mix of a couple different things. The fuel lines next to the drivers side cat gets REALLY hot so I think the trick will be to stop that from happening and then replace your EVAP system. Whats weird is there are several people on here that have said they have fixed it with just doing one thing like fuel pump or CC for example.
- Gas cap (didn't work last summer)
- Muffler (haven't test yet)
- Wrapped fuel lined with heat shielding (haven't test yet)
- 2 pre cat o2 sensors (haven't test yet)
Next up this weekend:
- Fuel pump
- Building heat shield
Then I'll order the CC, VSV and hoses:
I've been dealing with this issue over the years and I really believe its a mix of a couple different things. The fuel lines next to the drivers side cat gets REALLY hot so I think the trick will be to stop that from happening and then replace your EVAP system. Whats weird is there are several people on here that have said they have fixed it with just doing one thing like fuel pump or CC for example.
I have said this once and I will say it again. This thread needs some sort of poll or someone needs to build a spread sheet that lists all the things people have experienced and people have tried to determine repair trends. 
I've had it happen many times, always summer, with ethanol gas, usually lots of switch backs and tight curves driving... trails etc. Yesterday, was different however as it happened in Arkansas about 900ft, not at high elevation. To me it is exhaust/ambient air temp plus ethanol related. I am going to try that heat shield first. We had to move the camp stove a lot further away than usual last night, not trying to cook us for dinner. The question still exists for me however, did this not happen when these were new? We had ethanol gas back in 06/07 right, so would it indicate something is wearing out or functioning properly?
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Three things:
1. 100s have had the gas smell reported even when new you can find threads on this forum from the early 00s.
2. Hoses wear out which releases the pressure build up which reduces the pressure in turn lowering the boiling point of the fuel.
3. Ethanol actually increases the boiling temperature of the fuel, however it creates more fumes. Potentially, a larger volume of fumes creates more pressure inside which could force itself out through a leak where pure gasoline might not.
Another data point I was over 9000 ft this weekend with my fuel temperature gauge showing 125F and half tank of fuel and I had no boiling at all. The difference this time was I had 30% ethanol instead of the normal 10%. Ethanol does indeed raise the boiling point. I still had lots of fumes, though.
1. 100s have had the gas smell reported even when new you can find threads on this forum from the early 00s.
2. Hoses wear out which releases the pressure build up which reduces the pressure in turn lowering the boiling point of the fuel.
3. Ethanol actually increases the boiling temperature of the fuel, however it creates more fumes. Potentially, a larger volume of fumes creates more pressure inside which could force itself out through a leak where pure gasoline might not.
Another data point I was over 9000 ft this weekend with my fuel temperature gauge showing 125F and half tank of fuel and I had no boiling at all. The difference this time was I had 30% ethanol instead of the normal 10%. Ethanol does indeed raise the boiling point. I still had lots of fumes, though.
Thanks folks, you just saved me from buying a new gas cap. I've had this happen twice. Both at high altitude and bumping around a lot. Most recently above Bishop in the Coyote Flats area, which I saw previously mentioned. The pressure build up has been tremendous, and scares me with how much vapor comes out with some liquid too for awhile. Anything hot, or more dangerous someone smoking, nearby could easily cause a fire. I watched the vapor roil around in the air and some of it go low, and that, my friends is scary. I know these things and have seen my share of gasoline fires. I'd like to figure out how to deal with it, so it doesn't happen. My buddies aren't the patient type, and I would hate to have to stop to depressurize the tank regularly, because I'm not driving around while I smell gasoline. I worked in a refinery laboratory for quite awhile until 10 years back and tested a lot of gasoline. The initial boiling point is around 100 degrees. With this, California, where I live, and other states have their own rules regarding gasoline. In any case, here the winter gasoline has a high vapor pressure (about double the summer limit) so you can start the engine when it is cold. In the summer they lower the vaport pressure so you don't get vapor lock. They do this basically by adding or removing propane. The financial incentive to use as much propane as possible is enormous and they ride the high side limit to a hairs breadth. I don't know what numbers the tank pressure builds up to, but it's way more than it aught to be, I'm sure. The high pressure will keep it from boiling, but release that pressure and it does not surprise me you'll boil it. I don't understand how this could be "normal".
Cheers,
Joe
Seriously, I don't know what to believe. So many scenarios and variables. I experienced a large amount of vapors and gurgling last trail run. 77 degrees out, but the trail had steep incline. Elevation topped out at 6100'. Never experienced this before, and I've been on trail a lot.
- Thread starter
- #293
While ethanol does boil at higher temperature (i.e. has lower vapor pressure) than gasoline, blends have a non-linear relationship.
For blends below about 40% ethanol the vapor pressure is higher than gasoline. Probably explains why @J1000 was seeing better results with 30%. In order to market E10 the EPA granted a waiver on vapor pressure requirements for E10 as it could not meet the EPA requirement on gasoline.
The following graph is from the National Renewable Energy Laboratory which is part of the US DOE.
From the NREL report.
However, when blended into gasoline at relatively low concentrations the more numerous gasoline molecules disrupt the attractive forces between ethanol molecules and allow the ethanol to readily evaporate, raising the vapor pressure of the blend.
For blends below about 40% ethanol the vapor pressure is higher than gasoline. Probably explains why @J1000 was seeing better results with 30%. In order to market E10 the EPA granted a waiver on vapor pressure requirements for E10 as it could not meet the EPA requirement on gasoline.
The following graph is from the National Renewable Energy Laboratory which is part of the US DOE.
From the NREL report.
However, when blended into gasoline at relatively low concentrations the more numerous gasoline molecules disrupt the attractive forces between ethanol molecules and allow the ethanol to readily evaporate, raising the vapor pressure of the blend.
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Bomar
SILVER Star
I will say I run pure gas more than a mix and I put a heat shield on my fuel lines by the cats a last year and I didn't have any issues in Utah and CO last year like I had previously.
I also have a 40 gal aux tank
I also have a 40 gal aux tank
I replaced canister last year and still boiled at 12000 ft.......this year I will run all gas and report back........still have old canister if anyone wants it to inspect.
if someone really wants to you can put an extended banjo bolt on either side and an electric temp sender. That would be about a ten minute install and go drive, gauge taped on the windshield.
There are no temp senders stock. I think that's understood already.
Even better, put a temp probe off your VM down by the regulator and duct tape the meter to the windshield.
is there such a thing as a magnetic electronic temp sender with a BT transmitter? lol. I can think of all sorts of good things to look at if there was such a thing.
There are no temp senders stock. I think that's understood already.
Even better, put a temp probe off your VM down by the regulator and duct tape the meter to the windshield.
is there such a thing as a magnetic electronic temp sender with a BT transmitter? lol. I can think of all sorts of good things to look at if there was such a thing.
It happens literally every single time I think about getting in the truck during June or July and want to go off roading no matter the elevation. I have talked to several guys that ran heat shields and I have not heard anyone has had it come back after installing them. I'm going try that today and then I'm going to Colorado for a week, I'll post that what I find.
I live in WNC just above Atlanta, my house is at 2,200ft. When I used to commute daily to Atlanta (2 hours) i would hear a kind of boiling sound from the truck if the tank was full. I always chaulked it up to parking at an upward angle. However, I suppose that last 800' rise in the last mile might be a factor.
I wonder if there are mods worth having before you go on a trip at altitude?
this happened to me today
full tank
5000 ft
the gasfalls
full tank
5000 ft
the gasfalls
Don't mean to hijack the thread--but where are you all getting fuel temps from? I'm using OBDLink MX+ (which gets me all sorts of vehicle specific data, including AHC pressures, transmission temps), but I don't see fuel temp anywhere in that list. Did you create a custom gauge?
