Fumes in car? 83' 944

[astronomical]

All, I posted the air shutoff question but this needs to go another way I think.

My car smells like exhaust type fumes all the time. So much so that I have had to park it because I smell horrible after I drive it. So, I can't go to work at our Corporate office smelling like an exhaust. Now, today I took it to my brothers garage and we looked and looked and looked. NO LEAK! Does ANYONE have any thoughts on what might be going on. My brother had a theory that MAYBE back at the exhaust tip where there is a small space between it and the pipe connection is causing fumes to come up in around the hatch or something. I don't know though... we are at a loss. Someone please help me. I just got the car road worthy on June 2nd and I have already had to park it. :-(

Thanks! L.B.

[Rasta Monsta]

How is your hatch seal? Is the hatch itself solid (frame unseparated from glass)?

[astronomical]

My seal is horrid. The glass SEEMS okay from what I can tell. Maybe a slight bit of separation up near the very top near the sunroof but not enough to cause water leaking or anything. The seal though... in pieces and leaky on occasion.

[944Spec_bound]

I kept smelling fumes, I think this was the problem:


But seriously, other than melting my bumper pad, when I was running no tip on this aftermarket muffler I was getting fumes in the cabin, assuming from the poor seals in the hatch area. So, if yours is loose or cracked in the same area, I guess it could be doing the same thing. You can actually see in my pic the stains from where the heat and fumes were going up between the bumper and floor.

Also, are you sure it's exhaust fumes? My 84 had fuel smell issues for a while from a bad gas cap.

[astronomical]

Well, I can't say I am 100% sure it is exhaust and not gas. I have no A/C plus a smelly car so I am always driving with that window down. I just know it is stinky when I drive and when I get out my wife and son won't get near me until I shower. Really putting a damper on my driving enjoyment!

[Rasta Monsta]

Originally Posted by astronomical

My seal is horrid.

Horrid seal = exhaust in car. I should also add a corollary, used seal = ****e. . .buy a new one.

[astronomical]

Is the 104.00 one from Pelican about the best I will do?

[Rasta Monsta]

That is ballpark for genuine Porsche. . .

[astronomical]

Okay... I can get that and also maybe I should go ahead and replace that old gas cap anyways. I see they have a fuel cap seal for 8 bucks. Should I get that and replace that as well? Or is that even something you think I will be able to do on my own or with the help of my brother at his garage. We are not Porsche experts but if you all think we should be able to without it being a big ordeal I will go for it.

I love this site! You all are so helpful and informative. I will be posting A LOT on here over the next several months. My girl is in rough shape!

[astronomical]

Oh... do you have suggestions on this post... http://forums.pelicanparts.com/porsche-924-944-968-technical-forum/549243-power-windows.html ???

[Thunder-71]

I have a similar problem with my 1984 944 N/A. I smell a combination of gas and exhaust fumes if I open one or both windows. If the windows are shut everything is normal, no smell in the cabin at all. I have the car for 14 months and still can not figure out where the problem is. Seems like by opening a window a vacuum of some sort is created drawing fumes in mainly from the exhaust. I see black residue on top of rear bumper and on tail panel between the tail lights that can only come from the exhaust. I am annoyed enough that I am thinking of replacing the exhaust tip with one that will extend further out and point to the ground. I had a lot of cars thrue the years and never seen anything like this. Did Porsche screwed up somewhere on this?

[cam100]

Originally Posted by Thunder-71

I am annoyed enough that I am thinking of replacing the exhaust tip with one that will extend further out and point to the ground. I had a lot of cars thrue the years and never seen anything like this. Did Porsche screwed up somewhere on this?

I don't think extending the tip will fix the problem, unless you use a really long extension!
The aerodynamics of the car cause a low-pressure area just behind the rear hatch. This draws exhaust fumes up around the rear of the body. If the hatch is well sealed this is not a problem. If you have any leaks around the hatch, however, when the windows are open, this draws in the fumes that are swarming around behind the car.

[Thunder-71]

Originally Posted by cam100

I don't think extending the tip will fix the problem, unless you use a really long extension!
The aerodynamics of the car cause a low-pressure area just behind the rear hatch. This draws exhaust fumes up around the rear of the body. If the hatch is well sealed this is not a problem. If you have any leaks around the hatch, however, when the windows are open, this draws in the fumes that are swarming around behind the car.

Your comments confirm my suspicions about the hatch seal which is not perfectly tight. Hopefully I should be able to fix it even though it seems kind of hard to. My seal looks fairly good. I tried to make it latch tighter by adjusting the two lock pins but then the hatch pops open at the first bump. I may have an aged seal that lost its form (thicknes) so I will replace it and see what happens.
Thanks for your good input/advise.

[VII]

my rear hatch leaks and I'm sure my seal is not the best but I know my problem to be an exhaust leak where the cat should be. Even with my leak and running what smells to be a little rich, my clothes do not stink after a drive and my exhaust smell is easily identified inside the cabin. My muffler is tucked under the car more than it should be as well so it makes sense that I should have fumes as they can get easily trapped under the car. It sounds like you have a rich running engine that you need to look into or a very major leak; I just don't see a rear hatch seal allowing that much fumes to enter your car and then those fumes must having a bad mixture to really stink you up. It's worth looking into your 02 sensor while you're spending the money on parts. Best of luck.

[Davie Boy]

Originally Posted by Thunder-71

I have a similar problem with my 1984 944 N/A. I smell a combination of gas and exhaust fumes if I open one or both windows. If the windows are shut everything is normal, no smell in the cabin at all. I have the car for 14 months and still can not figure out where the problem is. Seems like by opening a window a vacuum of some sort is created drawing fumes in mainly from the exhaust. I see black residue on top of rear bumper and on tail panel between the tail lights that can only come from the exhaust. I am annoyed enough that I am thinking of replacing the exhaust tip with one that will extend further out and point to the ground. I had a lot of cars thrue the years and never seen anything like this. Did Porsche screwed up somewhere on this?

I have the same issue with my '88 924S. For me, it has to do with the removable roof. When I have the windows down and the roof popped-up, I get some exhaust flow into the cabin. I don't think it's that bad, but my super sensitive wife can't stand it. When it's completely closed, I have no problems.

.

[dogsharks]

Hi guys,

If you even have a 1/8" gap in the rubber seal around the hatch, the negative pressure formed by the spoiler and all will suck fumes in by the "station wagon effect". I had such a gap in mine, stinky smell, and all it took was a piece of black electrical tape to cover the hole, bingo. Then I later fixed it better with some sealant.

Regards,

Dogsharks

[wharlos]

Recently picked up an '88 944 with an obvious exhaust leak. Tig welded the obvious crack in the 1-4 exhaust header. It was a massive job but the car smells much better. It still stinks a bit at speed under throttle with the windows down. As a test, I ran a strip of duct tape around the back of the hatch and the problem went away. If your brother can't find leaks in the exhaust system, my bet is you have the same hatch seal problem.

Duct tape doesn't look good on a Porsche so we're back to making the hatch seal actually seal. While the hatch seems to be lined up to the opening, it doesn't even come close line up with the seal at the back of the car. It looks like an additional strip on the hatch itself has been removed. My hatch looks as though it has had new glass glued in at some point. Maybe the strip was removed then.

Any thoughts?

[cauzomb]

The rear hatch seal is a strip clamp "like tungue and grove" to the sheetmetal, ontop of the strip clamp area, there is a thicker O shaped padded sealing surface that provides the seal between the hatch and body.. there is also a seal on the hatch side below the wing that needs to be in good shape too.

It is common for the rear/bottom hatch seal to get damaged by loading/unloading cargo carelessly.. Some of them are a single "uncut" donut, others are a length with two ends that join near the center hatch lock..

Once the flexible gasket part of the seal is damaged or separated from the part of the seal that holds to the chassis, it will unzip itself, or someone may have just pulled it off because it was hanging out the back like a tail.

If it's missing the padded porschion :P on the outside edge you need a new seal, exhaust fumes are not good for you.. here's a picture I found showing both the metal clamp part and the padded part as intended http://i26.photobucket.com/albums/c103/arlo87/take4003-1.jpg

Standard household weather stripping might get you by in a pinch, till you can replace the seal there are also some universal stick on automotive foam seals that might do the trick

[VINMAN]

Also check the seals around the tail lights. Fumes will get sucked in through there too.

[968 GUY]

There are plugs in the side cubbies and spare tire well, they are small, but may let in some of the fumes.
Change that seal and adjust the latches. Clarks Garage has a lot of helpful info.
Ken