1971 Series 3 2+2 Rear Door Air Extractor Help

First of all, what does this thing do? Extract air, I know of course, but why and how? P.O. had sealed it up, and I want to make it functional again. Seems there’s an interior plastic piece with a couple of slots, maybe part # BD38987, 8, or 9. Can’t find one anywhere. Anyone have a lead? Thanks.

Hi Ferman, Most S3 2+2 owners will have closed off that vent at some point, because it is a source of exhaust fumes. In general most of us at some point have had a blitz to plug up all and sundry holes or gaps especially in rear one third of the car. Despite the appearance of a stream lined shape, sadly the 2+2 definitely has this tendency. So open up the vent but check carefully for fumes!!

The idea behind it is to get a flow of air through the car whilst moving. By having your front air vents open, pressure builds up in the cabin and the shape of the e results in a negative pressure area at the tail thus enabling the flow of air through and out. Fumes cannot come back in. If the car is standing still and provided the flappers are fitted and working on the inside vent, then again this will prevent any fumes from entering the car whilst stationary. Yes, by all means reinstate it, works well.

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Thanks for the advice. I have everything except the flapper piece. Now the question is where do I find the flapper piece? I’ve checked all the parts sources I can find but no luck. I’ve been getting fumes and will give the rear third of the car a good looking over to plug any openings.

Hi XJC, I understand the theory, but it doesn’t seem to work that way.If you look in the archives you will see what i mean.Have you had an SIII E 2+2 that was fume free?

Yes, have one now and no issues with exhaust fumes. Then, my sense of smell could be questionable I guess. :smirk:

Of course it doesn’t help to have a significant other who has some strange way in the past connections with the bloodhound line!

I’ve been wondering why my clothes smell of exhaust fumes when I’ve driven the E. I cant smell exhaust fumes while driving though, so it must be small amounts. These comments has confirmed my suspicion that exhaust fumes were entering the cabin via the rear door vent.

I can see that by having the front vent open and fan on, would generate a positive pressure in the cabin thus forcing air OUT the rear door vent. Only thing is, the air that enters from the front has been heated at least 5degC over ambient. If ambient is already in the high 20’s then that air is rather unpleasant. I thus prefer to shut that vent off and drive with aircon on (which circulates cabin air only).

I’ll block off that rear door vent just as an experiment.

Hi Philip, While you are fixing the rear vent, I suggest that you check for other sources of ingress of exhaust fumes. The whole area of the back storage area should checked very carefully for holes…ones that might have had a plug in place only later to have fallen out or just removed! Also check under the mats in the rear for small holes. Lastly, also check for the integrity of the rear hatch seal…if its been around a while a new one might help.While doing that make sure that the rear drainage vent is still free of blockage! happy hunting.

Thanks John, this car had a bare metal rebuild quite a few years ago but it was an outstanding job, Every nut, bolt, pipe suspension part that could be anodised, was. All rubbers are fresh, so I doubt there are any holes there should not be, but I will have a very careful look next time I’m under the car.

Getting to that vent in the back door seems to require removal of the inner door trim - something I loathe. So, I’ll just tape the hole closed, if only to verify that doing so solves the problem.

So, I sealed off the rear door air extractor - actually double sealed it both outside and inside. But still getting fumes, so getting ready to the the detective work to find and seal all rear openings. I usually keep the heater fan running around town - hopefully that helps some. I’ve asked my mechanic to assure I’m not running too rich, which is what it smells like. I do know it runs really rich when the choke is on - it even spits wet carbon, which black spots the drive. LOL! Will appreciate any advice.

Ferman, I wouldn’t be to concerned whether you are running rich or otherwise…clearly you have a leaky car where outside fumes are entering the car! You need to remove all stuff from the rear of the car. Also remove the the rear seat and carpets and look for holes. Also cast a beady eye over the firewall area.A thorough search will pay off, and good luck with this!

I’m not an S3 guy but exhaust smell has been reported in virtually all models. What has already been said is the way it is. The fumes are hanging out around the rear 1/4 of the car or so and if a window is open even slightly or significant leak in the interior low pressure is created and it will inhale fumes from any hole that exists. I had them on my OTS from leaky exhaust gaskets in the engine compartment and leaky plugs and grommets in the interior even at the firewall. Also had fuel smell for the same reason, fumes migrated from the boot to the cabin because the windows didn’t seal tightly so always low pressure in the cabin. So need to check for exhaust leaks forward of the rear if they are there then fumes can come in from forward locations. Checking the read door seal can be easily done by using a 2" or so strip of paper, closing the door on it and ensuring there is friction to pull it out. Do this all the way around the door, you will be able to tell how your seal is fitting.
pauls