Smell of gasoline in cabin of 380SE??

[Lundbye]

I have a beautiful 1984 380SE with a nasty problem:

When I open a window (just one), the slight underpressure in the cabin pulls in gasoline vapours from the engine room.
(When more windows are open the problem goes away as the pressure is levele. Also it should be noted that the problem is not there when all windows are closed. Again I assume it is because there is no underpressure in the cabin then)

I heard a rumour that this may be due to the gas-pipe running from the gas tank to the engine, being pulled apart at a joint behind the glove compartment by the underpressure.
I have now tried two Mercedes mechanics with no luck.

Have anybody experienced or heard about this problem?
Or have other suggestions?

best wishes
/Lundbye

[psfred]

Check all the fuel system for leaks (I had a hose leak at the line to the fuel distributor on the TE, had to replace it). There is no hose that will pull apart under slight underpressure in the passenger compartment, what you are smelling is a serious fuel leak in the engine compartment with vapors being drawn past the seal at the firewall into the suction for the climate control, or in the window.

Possibilities are pressure regulator for the fuel injection, leaking EHA seals (or EHA itself), leaking fuel lines, leaking line to injector, or leaking fuel distributor.

There are also some connections under the body, I believe, on the return line.

If this is much worse just after filling the tank, the vapor control system has a leak, too.

Peter

[126nut]

My 89 had a seeping injector line. I had failed to adequately tighten one on the recent rebuild, the fuel will really reek when it is being boiled off the intake of a hot engine.

[Lundbye]

Thanx a lot for your input. Do you have any idea as to why the vapours only - and very strongly - enters when there is an underpressure in the passenger compartment?
Peter (psfred) writes:
"Vapors being drawn past the seal at the firewall" - could you please explain how the firewall works?

best wishes
/Lundbye

[psfred]

There is a large rubber seal on the front "firewall" -- actualy just a partition-- in front of the heater intake under the hood. If you have a leak, and that front seal is bad or displaced, the fumes will go right into the climate control intake, blowing into the car. If it's intact, it should keep any vapors in the engine compartment isolated from the climate control.

A really big leak (spray from a fuel supply line at 50 psi, for instance) will probably get vapors into the interior anyway.

Peter

[eteller]

Had the same problem, tried everything, repaced all the vac lines and the emission canister lines (they WERE cracked) but the problem was the gas cap. A $10 dollar fix!!

Ed Teller
85 380SE