I will just tell you that I had this identical constellation of problems in my 1997 EVC that started in July 2014 when my van had 139,000 miles.?
I replaced the fuel tank cap and associated seals and hose clamps. I replaced a bad check valve and the gas tank with a new one in July 2014; then replaced the gas tank again under warranty (for the 2014 tank) in July 2015 and I replaced the carbon cannister at the same time. The EVC then had 147,000 miles. I also removed the belly pan to give better ventilation to the engine so that the heat is not all directed around the gas tank.
The problem described did continue, despite all this. I am told by my current mechanic that this problem was fixed in the 2000-2003 EVCs, as the vapor recovery system was changed substantially and there is no longer a tail on the carbon canister that exhausts fumes directly onto or into the frame when the canister cannot absorb all the vapor.
Gas fumes can be caused by a variety of things. Some of those things, are fixable. I am going to paste below a string of comments from the VW list in 2014-2021 on the topic, and you will see the comments, a fix or two for certain causes, and the frustration that this has caused:
Wolfgang Baudler, EV list, August 29.
I had the same problem as the original poster with fuel fume smells inside and outside on my 1995 EV. Smell was intermittent, seemed to depend on temperature, weather etc and also was more pronounced when going uphill.
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In my case it turned out to be a broken breather tube, the line connecting the top of the fuel tank with the EVAP canister.?
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It was broken at an inaccessible location near the top of the tank. Took a long time to track this down, but once I have replaced that breather tube the fume smells went away. The whole line was very brittle, so possible that this might be the cause for others as well.
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I managed to replace it without dropping the tank, but you will need to cut the carpet in the cabin for access to the top of the tank. It would be much easier to inspect and replace with the tank dropped.
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Part number for the 95 is 7D0-201-059-C?
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Wolfgang
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From: "websailn2@...?[ev_update]" <ev_update@...>
To:?ev_update@...
Sent: Wednesday, August 20, 2014 1:51 PM
Subject: [ev_update] Re: Fuel Evap System for 1997 Eurovan
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There are a few diagrams of the system in the Bently Manuals, but not much of a description of operation. Without doing some more study here is a general summary off the top of my head of how things work:
In your fuel tank, you have liquid on the bottom and vapor on top of that. As you refill the tank, adding more liquid, the vapor needs somewhere to go. In the old days, it just vented into the environment around the side of the fill nozzle. Now, for environmental reasons, it's forced into a charcoal canister, where the vapor is adsorbed. Later, when the engine is running and up to operating temperature, the canister is connected to the intake manifold by a valve that allows the vapor to be drawn off and burned, cleansing the canister for the next refueling cycle. There are a number of check valves in the filler neck assembly that allow this to happen as described and you can stare at the Bentley diagram for a long time trying to figure it out.
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One issue regularly reported, is overfilling the tank thereby pushing liquid into the canister. The liquid turns the charcoal granules into a solid briquette which will block the canister, sending the vapor out around the nozzle like the old days. You'd smell it, but also likely experience the gas pump nozzle clicking off a lot. Doesn't sound like you have that problem.
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Alternately, the canister may have lost some of it's "storage" capacity. It may be "full" because the stored vapor is not being drawn off because of a blockage in the system or a failure of the vapor recovery valve. You'd smell this too - the canister is behind the driver side wheel and has a breather tube that would expel any excess vapor that couldn't be adsorbed. However, I recollect there is a self test of the system on start up so you'd get a check engine light if this is the problem - I think.
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Finally, over time, the charcoal granules get pulverized so there is more void volume in the canister, less adsorption surface - again less vapor storage capacity. So any vapor that couldn't be adsorbed would also pass out the canister's breather and you'd smell that.
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One more obscure thing: some people have mounted things under the front seat - stereo amps and such, inadvertently drilling through the top of the tank. That would give you a gas smell but most of the time though, not just during refueling.
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I have heard of the trick of leaving the gas cap off to "dry out" the canister but I don't think this actually works. One, I don't believe the system check valves are oriented to allow this and two, a damage canister (solid brick or excess void) can't be restored with just an airing out.
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If you problem is persistent, a new canister is probably the easiest solution. If it isn't affecting drivability, it's just an environmental issue.
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OK, lost my head on this post. I need a life.
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Regards,
Duane?
2000 EVC
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Thread on the issue on Eurovan FB page Feb. 18, 2021
Hello, I own a T4 shop and we see this often. We see dirt/debris/insect nest clog the breather lines, cracks in the tank and/or hoses. A saturated canister / stuck purge/evap check valve can also cause this.
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Tom Smith
My 2002 is doing the same thing currently.??
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Terry Schmerk
My 99 had the same problem..replaced the gas tank..problem solved
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Chelo Cobian
Terry Schmerk cost?
Like
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Terry Schmerk
Chelo Cobian the tank was only 75...out of a used one from a scrap yard...this was in Toronto..shipping for it was about the same amount
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Chelo Cobian
My 2000 has that same smell...sometimes. had shop check it out and they found no cracks or leaks and everything working fine??
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Obaid Zamani
Snow and ice / Debris dirt there’s breather lines by your rear wheel for your gas tank I had this issue years ago over the winter in northern Virginia
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Gary Lewis
I had a the same issue. My issue was pressure buildup in the tank when I removed the cap just as you stated. I could smell gas at times before removing the cap. It turns out that there is a small valve that gets pushed in when the gas cap is inserted. The gas vapors are then released into the charcoal canister etc. All i had to do is carefully bend the flat metal v shaped valve out a bit so when the gas cap was inserted the valve would open into the line and release the tank pressure. It's on the left inside. Hope that makes sense.
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Chelo Cobian
Gary Lewis anyway you can take a pic and point to it?
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Mark O'Neil Conner
'95 EVC, here. Been to this movie. My mechanic replaced the fuel line, it was badly corroded. Problem solved.
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Corporal Ninny
I have a ‘97 with 190K had a similar issue and replaced my gas cap which solved the problem - I bought this cap off ebay but don’t see it listed anymore it was just under $15
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