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Gas Smell and High Outside Temperature

I am the original owner of a 1997 Ford Explorer that now has over 250K miles. In very high temperatures (above 105F) the vehicle has an extremely strong fuel odor (similar to raw gas) after it is driven. The dealer stated this is normal in Las Vegas due to fuel expansion and there is nothing that can be done. Is this true and is there anything I can do?

Dealer? For a 12 year old truck? Why?

And the diagnosis is BS! There is fuel expansion and vaporization happening, but EVERY gas-powered car and truck sold in the US in the last 20 years has a charcoal canister that is supposed to capture these vapors, and hold them until the engine purges them. If the vapors are escaping, there is a problem.

First thing to check is to find where the vapors are escaping from. The usual suspects are the charcoal canister itself, or the hoses connected to it. The canister vents underneath, and if you smell vapors here, it probably needs to be replaced. If the purge circuit (evap system)was leaking, you’d get a DTC, and the check engine light would be on. This would be true of the tank leaking, too.

Thank you for your help and quick response. I only moved to Las Vegas last summer due to being relocated here (I am in the military). I took my Explorer to the dealer because I never encountered this before and being new to the area, I figured they’d have the most experience with this type of problem.

Based on my own troubleshooting (the strongest smell seems to originate from underneath, near the canister) I actually did replace the charcoal canister. This seemed to help but the problem still persisted. I never got a DTC / check engine light.

Given what your wrote, at least now I know this is not normal. I’ll double-check all the hoses & vapor management valve. Thanks again, I truly appreciate your insight!