I have a 1986 Volvo 240 DL Wagon with about 190k 5Spd manual Trans.

When I'm driving sometimes I smell fuel/gas coming from the front/under the hood.

How is it that you know they are coming from under the hood? I have seen several 240's that you could smell fuel on when you rolled down the window. It was coming from the deformed filler neck where the gas cap screws on. Don't ask me how you can smell it when you are doing 40+ mph down the road but you can and I have had plenty of customers over the years complain about it too. If it is in fact under the hood it should not be to terribly tough to find.

Mark

Mark
Thanks for that info! I was stumped till now. Can I assume another filler neck would be the cure?
Todd

Well, check the entire car over first and rule everything else out and then go back and take a whiff around the fuel door and if you smell gas then it is probably right there. Don't get me wrong, there are other places it can and will leak fuel but the filler neck is the most popular.
Take a look at the neck and see if it is getting tear drop shaped. People lean on those fillers while they are doing it and after years and years they start to deform and the only fix is a replacement.
The only other way I have used to diagnose these leaks is with a smog maching. I would set it on manual mode and take the sniffer and wave it around the filler and if I came up with HC (hydro carbons) then I knew it was leaking.

Good Luck,
Mark

Oh yeah, and remember if you are doing a filler neck on it to wait until it is darn near out of gas before you drop the tank.

Mark
Thank you again. I had not put the "hogged up" filler neck together with the open the window and smell the fumes syndrome. Your suggestion was brief and I believe on the mark as I had eliminated the fuel delivery and exhaust systems. Thanks again for showing me to the fuel storage system. May something even more helpful happen for you.
Todd

Mark is bang on. I had exactly the same symptom, and equally couldn't believe it could be an out of round filler neck. My mechanic put channel locks into the neck, pulled it into round, and I never had the problem again.

--
David Armstrong - '86 240(350k km?), '93 940T(270k km), '89 240(parts source for others) near Toronto