Gasoline fumes in the trunk

olddog · #1 (**permalink**) 09-02-2007, 02:20 PM

When I purchased the car the previous owner told me about this. Previous owner had replaced or worked on most if not all of the hoses. He was the 2nd owner. He said he was never able to find any leaks. I assumed it was in the carpet.

I replaced the carpet (tried to shampo it but it still stunk). I cleaned the trunk up left it open a few days and there was no smell. Put the carpet in, thinking it was fixed. A week later and the trunk was full of fumes when I just opened it.

I do not think there is a fuel leak. I can smell some fumes around the gas gap. I suspect that the trunk lid does not seal up tight and the fumes are leaking in from the cap.

Does this sound plauseable?

Blas · #2 (**permalink**) 09-02-2007, 02:54 PM

Where is the tank vent plumbed to?
Any leaking at the sender?

olddog · #3 (**permalink**) 09-02-2007, 07:35 PM

Tank vent goes into the passenger rear wheel well. It is simply an open line turned down. I put a temporary plug in it to see if that made a difference. Didn't help. Don't think it hurt either. I would like to put some type of filter on it to keep unwanted things out.

The sending unit and fuel pump (EFI) all seem dry. I checked it pretty good while the carpet was out. The hoses all look new. All connections seem tight.

cobred · #4 (**permalink**) 09-02-2007, 07:53 PM

Try putting fuel in the car with the trunk open and looking at the underside of the filler with a flashlight. You may see fuel seeping down the neck and wetting the carpet.

Silverback51 · #5 (**permalink**) 09-02-2007, 07:56 PM

Quote:

Originally Posted by cobred

Try putting fuel in the car with the trunk open and looking at the underside of the filler with a flashlight. You may see fuel seeping down the neck and wetting the carpet.

Use an explosion proof light.

Blas · #6 (**permalink**) 09-02-2007, 08:20 PM

Wrap any fuel connection in the area with a paper towel or some other absorbant paper and masking tape....including the vent tube end - lightly, fill the tank and take a little ride...check each piece of paper on your return for fuel spots and wetness... you will eliminate these areas from your search. The leak could also be under the car and splashing back to the trunk area. Split hose, filter, pump, hard line....

olddog · #7 (**permalink**) 09-02-2007, 08:21 PM

Since changing the carpet, I have not added any fuel to the tank. Tank was nearly full (15 miles) when I replaced the carpet. I drove it about 40 miles after and then it sat all week.

I'm going to air it out good over night. If the smell clears up enough, I'm going to see if I can find a spot where the carpet smells like fuel got on it.

pgermond · #8 (**permalink**) 09-02-2007, 08:33 PM

Quote:

Originally Posted by olddog

Tank vent goes into the passenger rear wheel well. It is simply an open line turned down. I put a temporary plug in it to see if that made a difference. Didn't help. Don't think it hurt either. I would like to put some type of filter on it to keep unwanted things out.

The sending unit and fuel pump (EFI) all seem dry. I checked it pretty good while the carpet was out. The hoses all look new. All connections seem tight.

You want to maintain that vent. You might check to make sure it's not plugged up. Does the tank have a sending unit mounted on top? Does it only leak/smell when the tank is filled to capacity? I used Permatex Aviation form-a-gasket on all areas of the tank and have never had an issue.

Good luck.

olddog · #9 (**permalink**) 09-02-2007, 09:01 PM

Quote:

Originally Posted by pgermond

You want to maintain that vent. You might check to make sure it's not plugged up. Does the tank have a sending unit mounted on top? Does it only leak/smell when the tank is filled to capacity? I used Permatex Aviation form-a-gasket on all areas of the tank and have never had an issue.

Good luck.

The tank has a sending unit on top.

The tank has an EFI pump also mounted on top.

Both are accessed through the trunk.

The only place I could smell gas fumes before installing the new carpet, was at the cap. If the trunk lid is not sealed up, could the fumes be entering this way?

pgermond · #10 (**permalink**) 09-02-2007, 10:22 PM

I don't know, I can't visualize your setup. Is the cap a screw on our the original type. I would, however, make sure you have the tank vented adequately.

vettestr · #11 (**permalink**) 09-02-2007, 11:45 PM

Hey olddog,
If you can post a photo of fuel cap it will save a bunch of ??
If you have the standard flip top fuel cap then does it have an internal cap inside that, is it a sealed or a vented cap? Is the vent hose run outside the body where fumes will not fill the trunk or cockpit? Does it have a fuel filter on the end of vent to keep crap out (this is not for fumes)?
If no leaks in fuel cell or hoses it leads to vent hose and vented fuel cap. You can get a rubber plug that expands when you turn a wing nut from local hardware store like Ace. Place this plug in the filler hose end for time of checks only and extend vent hose away from car 6 to 8 feet just for checks. You can not plug fill hose completely and the vent hose completely for long (days) as temp changes will pressurize the cell and that is not good as it will leak fumes for sure.

olddog · #12 (**permalink**) 09-03-2007, 10:13 AM

This will be quick, as the wife has plans. Gotta go to a birthday party.

The smelll seems to be near the fuel pump. My thought is to plug the fill cap as Vettestr described. Soap the area (and every connection for that matter), then pressurize the tank through the vent hose (low pressure - maybe 2 psi).

Sound affective and safe?

I may not be able to get to it until tomorrow night. If I don't get it figured out, I'll post pictures of the entire setup.

Power Surge · #13 (**permalink**) 09-03-2007, 10:21 AM

If you have an open vent, you're going to get fumes. My car is the same way, and there are always fumes around it when it sits. You can't really block the vent off, because you need a place for air to enter the tank to displace used fuel. If you want to try to cut down on fuel vapors, maybe try installing a carbon tank to run the vent line to. If you are EFI, you can even put a canister purge valve to it also, and pull the fuel vapors back into the intake.

CHANMADD · #14 (**permalink**) 09-03-2007, 10:22 AM

What is the tank made of? I have had the same thing for years and I am now convinced that the polyprop tank is sweating itself. Anyone else had this??

rbray · #15 (**permalink**) 09-03-2007, 11:00 AM

Is your fuel filter in the trunk? Mine Fram fuel filter is in the trunk and I think that is where I am getting the fuel smell from in my trunk.

Rick Parker · #16 (**permalink**) 09-03-2007, 11:05 AM

Russell hose has been known to allow vapors to permiate the hose wall.

CHANMADD · #17 (**permalink**) 09-03-2007, 11:09 AM

My fuel filter is up front,electric pump at back ,but on the frame in the diff area.

MaSnaka · #18 (**permalink**) 09-03-2007, 12:12 PM

I have heard some rubber fuel lines weep. It doesn't explain the trunk smell but I thought it was worth mentioning. Good luck!

John

Dwight · #19 (**permalink**) 09-03-2007, 05:10 PM

If you install a filter in the vent line it will restrict the vent. It will not allow air the escape when fueling the car. Been there, done that. Do not install a filter on the vent. Good idea that does not work. It takes an hour to put 15 gallons of gas into your car.

Dwight

olddog · #20 (**permalink**) 09-03-2007, 08:05 PM

Ok I pulled the carpet back and put toilet paper around everything. I also pulled the plug out of the vent line in the wheel well. I drove about sixty miles (took every kid at the B-day party a ride. I checked the trunk frequently. Nothing got wet. Then I filled the tank on my way home. I checked it when I got home. Still nothing is wet. I'm puzzled.

I tried to up load pictures tonight but failed misserably. It keeps saying that the pictures were successfully uploaded. I keep searching for them and cannot find them.

Oh yea its a metal tank - I think its steel. Fuel filter is on the frame bellow the trunk. I'll look around under the trunk next chance I get.