What are the major causes of gas fumes in the 924/944? When I got the car the shift boot was missing so I replaced that and it is sealed off. The rear trunk seal has a rip in it, I tried putting some foam tape temporarily. I can only smell it in the car above 20 mph. Any other areas to look? I checked out the exhaust already for leaks - none.

 

Areas that I would focus:

>cracks in exhaust manifold (common)
>hood seal (located just forward of the battery/fuse box area)
>rear hatch seal
>exhaust system leaks (muffler, cat, pipes)

 

hmmm i thought that the fumes were part of the 944 experience...

 

'But Homer! The car is filling with...'
'I know, I know..ranch dressing'

 

Also could be a leaky injector. Hope you find it!

 

What everyone missed so far: the strip caulk on the rear lights. I had a MASSIVE amount of exhaust fumes coming in the car (with the sunroof open and the windows closed - makes the most negative pressure inside). I tried everything. Including a strip of tape on the top of the rear hatch (covering where the glass meets the frame, which did help some...so I know I'll need a re-seal). But 90% of the fumes coming in were from the tail lights. It's an easy job. Take them out, scrape whatever crusty bits of goo are left on them off, and put some new strip caulk on. You can buy a box of it at NAPA for like $15, and it's enough to do the job about 10 times.

While you have it, you might as well re-seal the blower unit under the hood. It uses the same stuff, and if you taillights are nasty, you know that will be also.

 

20+yo car + 10+yo forum = topic covered only a few times..

I'm not sure if the search function works over in HI. At least attempt to complete your homework.

 

Are you intentionally trying to be rude to a potential new Rennlist member, or am I just being dense and failing to see your joke or sense of humor?

"Speedtek" Are you smelling raw gas or exhaust fumes? At what times do you notice the smell? After filling up ? Highway speed or when stopped?
Exhaust smell can be from leaking exhaust manifold or rear hatch sealing issues or like DarylJ said; seals around tail lights. Raw gas smell could be from a lot of areas. Let your nose do the talking. If raw gas is smelled after filling up, it could be the gas overflow drainage hose in the right rear "trunk" fender well came loose and is allowing fumes and dribbled gas to enter the cabin through that small rubber grommet just below your gas cap. Another source for raw gas fumes is the seal around the fuel level sender. Take out the rear molded carpet and check for fumes/leaks at the sender.
A neat way I've learned how to check for air leaks in door/hatch seals, etc., is to have a buddy drive the vehicle at highway speed with the windows closed, then you blow cigarette smoke at the suspect seals. The smoke will gravitate towards the leak and you can detect where it's being drawn out. Probably best not to do this test if you're smelling raw gas though!

--Lizard

 

I smell it above 20 mph. I suspect the rear seal is bad BUT forgot completely about the taillights also! I am also missing the Hatch lock seal and will replace that also.

THANKS! I will check that tomorrow.

 

I had the exact same problem on a 1983 944. I resealed the rear lights, installed a rear hatch seal, had no exhaust system leaks and still had such a strong smell of gas in the car that my wife would not even ride in the car. What I finally did that fixed the problem was replaced the Cat. These cars are getting old and it does not hurt to check all of these things, but it is probably a tired poor working cat. Good Luck!

 

Check the rubber shift boot. if that's torn, that'll allow it in.

or if in a similar case to the turbo, the turbo wasn't bolted to the downpipe anymore... everything under the intake manifold was sooty and black, and I was suffering some WICKED heat soak.

 

People have pretty much nailed it.

All I have to add is: You can't smell CO by itself. These issues NEED to be taken care of, considering you're stuck in a small car with a deadly chemical circulating.

 

it's the hatchglass seperated from the frame, thats the first place to check

 

Nope. there are many many other places to look than a tiny-*** opening. like a gaping hole in the exhaust, seals that open 1/4 inch or more around the hatch, a 4 inch tear in the rubber shift boot, etc. but the hatch separation generally isn't the problem with exhaust entering the cabin.

 

I think my 924S has a leak in the exhaust manifold, headache central in my ride with the roof open. Just kind of curious (and afraid to ask) if there is a reasonable way to patch a crack, if that turns out to be the case, and if I need to replace the header, can I do it with the motor in the car? :-)

Morrie