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> I have persistent gas! No, I mean there's always gas fumes in my car, but it's really noticeable >when I fill up. Have you run into any others who have had similar problems? I have no noticeable >gas leak, so I'm wondering about that charcoal canister and gas recirculation system. My manual >only makes slight reference to it. Anyway, could you circulate this question or post it in the >newsletter?


This has been the number one problem with owners of E3s for about the last 10 or 15 years or so. I'm going to include in issue #20 or #21 of the newsletter a long epistle on how to rid your car of the gas smell. It is purvasive in all E3s, overwhelming in others, and about 5 factors contribute to it. Quite simply, you have a leak somewhere, probably in the trunk, and the fumes are being drawn into your interior via the fresh air vents which connect the trunk with the passenger compartment.

Bear in mind that some of the early cars did not have an overflow tank, a recirculating charcoal canister, and merely utilized a vented cap. Most of these cars were converted by dealers over time, some where not. I've seen both.

The leak is either originating from the tank due to rust along the seams, from "craze" cracking of the tank (microscopic but big enough to release fumes) or from one of the two hoses which are attached to your tank: either the fuel line or the gas recirculating overflow tank hose. The latter is particularly brittle and usually always cracks. If I were you, I would do the following:

  • Remove and replace the overflow tank hose, it connects the gas tank with overflow tank, which is located in the trunk, bolted to the right inner fender well. The hose originates off of a nipple at the 4 o'clock position of the filler neck on the inside of the trunk; (as if things weren't complicated enough, some E3s do not have the overflow tank, hose, or filler neck nipple);
  • Remove the gas tank trunk floor cover and inspect the fuel line. R&R if cracked, etc.;
  • Inspect the rubber grommet seal around the filler neck behind the gas cap cover/license plate. If it's cracked or worn, replace it;
  • Visually inspect the gas tank for rust around the mounting bolts. If it occurs, it usually occurs around the rear quarter panel. The seal BMW AG used is sponge and holds water like one!
  • Ensure you have the correct NON-VENTING gas cap on your car. This is easily identifiable, though I don't have the manual here at work (!) so I can't tell you the difference right now;
  • More than likely the charcoal canister is not the problem.

As I said, the E3 has a unique "free flow" ventilation system which draws fresh air from the C-pillar vents and under the hood, freely circulating it through the passenger compartment and the trunk, so if you have a leak in the trunk, you're going to smell it right away. I would look there for your problem.

If you do all of the above and still have problems, I would re-seal the tank using a sealing kit. Tom Van Gunten recommended a kit Sears, Roebuck and Co. sells which I've used (and am going to use again in about a month). It works well and is fairly cheap, however, some people have taken their tanks to Radiator Repair shops and they've fixed them (i.e., washed out with acid, re-sealed, etc.) for about $50.00. A bargain, really.

This is sort of quick and dirty, but I knew you couldn't wait. Let me know what you find out after you've done all of the above.

William Gau, Coordinator, Senior Six Registry



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