My gas cap gave up the ghost at the same time bank 2 sensor 1 gave out. Replaced the gas cap and i'm not witnessing any pressure build up when i open the gas gap now.
Gas tank building excessive pressure & fuel smell. Dangerous for sure! Why does this happen?
- Thread starter 2001LC
- Start date
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First time to experience this and this is my fair share with the following driving conditions:
• Location: Mt. Charleston Southern Nevada (45 mins away from Las Vegas)
• Humidity: 8%
• Road grade %: varies from 6% - 9% steep grade
• Outside Air Temp: 116°F (from the foot of the mountain)
• Road speed Limit: 55MPH (Kyle Canyon Road)
• Ave. Coolant Temp: 201°F - 203°F (running at 55mph)
• Ave. AT Pan Temp: 176°F - 181°F (running at 55mph)
What’s on the cruiser:
• 2006 260k miles LX470.
• 275/70r18 tires, aluminum wheels.
• rock sliders (55 lbs. give or take approx)
• aluminum + pair of lights (70 lbs. give or take approx).
• no winch yet.
• factory radiator from 2006 (I know it’s due lol)
• TB/WP done 30k miles/4yrs ago.
• I wrapped the gas lines with heat shield tape - I think I may need to re-do this with a better quality product.
• no coolant leak anywhere.
• no CEL at all.
• Location: Mt. Charleston Southern Nevada (45 mins away from Las Vegas)
• Humidity: 8%
• Road grade %: varies from 6% - 9% steep grade
• Outside Air Temp: 116°F (from the foot of the mountain)
• Road speed Limit: 55MPH (Kyle Canyon Road)
• Ave. Coolant Temp: 201°F - 203°F (running at 55mph)
• Ave. AT Pan Temp: 176°F - 181°F (running at 55mph)
What’s on the cruiser:
• 2006 260k miles LX470.
• 275/70r18 tires, aluminum wheels.
• rock sliders (55 lbs. give or take approx)
• aluminum + pair of lights (70 lbs. give or take approx).
• no winch yet.
• factory radiator from 2006 (I know it’s due lol)
• TB/WP done 30k miles/4yrs ago.
• I wrapped the gas lines with heat shield tape - I think I may need to re-do this with a better quality product.
• no coolant leak anywhere.
• no CEL at all.
Ikr, it was actually 116-118°F really arid air. With the most recent projection by NWS in the Death Valley to go up to a record 131°F++ temps, I wouldn’t be surprised if we get another 120°F++ temps here again.
While I was driving from Henderson NV to Kinman in AZ in the middle of summer I experienced the same thing on my 92 Prizm. I pulled into a gas station on the AZ side and experienced the same.There was a fuel heater line (copper) fused to a coolant line running into the throttle IAC. I later disconnected it thinking the issue is over!
Well I was wrong, I sat in the car with AC on to get the inspection done few days ago for nearly 50 minutes out in this hot summer, and noticed the same. Upon inspection, everything inside the engine bay is extremely hot so does the fuel rail. This is what causes the heat in the fuel system. I am planning to insulate the fuel rail sometime soon.
Gasoline auto ignites above 250 C so we got some room there, but better to be safe than sorry.
Well I was wrong, I sat in the car with AC on to get the inspection done few days ago for nearly 50 minutes out in this hot summer, and noticed the same. Upon inspection, everything inside the engine bay is extremely hot so does the fuel rail. This is what causes the heat in the fuel system. I am planning to insulate the fuel rail sometime soon.
Gasoline auto ignites above 250 C so we got some room there, but better to be safe than sorry.
awesomeissquid
SILVER Star
Isnt the fuel rail hard mounted to the vehicle? I have been thinking about how this can be improved over the past few weeks, but I do not think the mounting point can be adjusted since that is what holds the injectors onto the fuel rail. There are two parts of the heat transfer equation increasing the fuel rail temp - conductive heat from the 2x mounts on each side and convection heat from general engine bay temps. We might need to know where the primary source of heat is coming from. If it is from the mounts through conduction, insulating the fuel rail actually increase the temperature since the heat can not be released into the ambient air.
The rail is longer and narrow so there is a much larger surface area exposed to the heat inside the engine bay than the conduction from the mounting points. In fact two nylon bushings are used to secure the fuel rail to the cylinder head so the condiction is minimal. I am planning to insulate the rail with those non flammable heat insulators used under the hood.
Is getting a new gas cap gonna help with this issue?
awesomeissquid
SILVER Star
Ah, you are correct! I totally forgot about the nylon bushings. So yes wrapping the fuel rails may improve the fuel temperatures especially if you are also relocating the the rear fuel line off the engine block like @J1000 did. It would be an interesting thing to test.
@J1000, did you ever test or think of testing insulating the fuel rail itself? Seems you would have considered that in all the testing you did so I would be curious to hear your thoughts.
- Thread starter
- #871
Post all you can, of outside and in.
No I didn't do anything to the fuel rails. Didn't seem worth it to me.
The #1 thing I did was to insulate the rear passenger corner of the gas tank itself. The factory heat shielding is missing from that location and it is also very close to the exhaust.
I just did 6 miles, no traffic with AC on and the fuel rail temp has risen to 57-60 C: The lower radiator hose was at 60 C and the ambient temperature is 36 C. I think the engine bay temp will teach about 90 C or more when parked/slow traffic with AC on. Since Gasoline is a mixture of many different hydrocarbons (Hexane boiling point 69 C, Heptane boiling point 98 C and Octane boiling point 126 C). Hexane will boil first at 69 C. Some of these gases that boil at low temps will escape into air via the canister vent which is a loss of MPG.
Insulating the metal parts of return fuel line is therefore a good idea!
Insulating the metal parts of return fuel line is therefore a good idea!
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Idk, the guy who solved his issue is here saying he did so without modifying the fuel rails at all. I'd be inclined to follow his advice from this thread.
Bold claims without much evidence leads to reaching for evidence to support the claim, rather than solve the problem.
Bold claims without much evidence leads to reaching for evidence to support the claim, rather than solve the problem.
Eyedaho
SILVER Star
I have wondered about that myself. I have a new one sitting in the garage, but I haven't installed it yet. I don't think it's easy to access through the fuel pump access plate is it?
I have the tank out on mine at the moment. I'm looking to replace everything on top of the tank while I have it out.
Unlikely - Both @87warrior and I have experienced this issue with a new pressure release valve.
- Thread starter
- #879
Heat shielding is helpful and can reduce or even prevent fuel boil. Installing heat shields and fuel line coolers, is not new. They treat the symptoms.
But it is not the same as solving the issue.
I had basically everything fuel-related replaced and still had issues...
Gas tank building excessive pressure & fuel smell. Dangerous for sure! Why does this happen?
I can not duplicate mine. Some hot days at sea level, some low elevation mountain driving, some regular driving on the highway on a 70° day. The worst was an 85° - 90° day on I-85 in north GA headed south. Could hear it at the gas station. Had an eighth of a tank or so left and it vented like an...
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