Fuel smell
hello everyone, I’ve been chasing a fuel smell in my car for a while now and haven’t found any luck yet. It mostly happens when I’m driving with the windows down, but I’ve also found it happening when I have a full tank of gas. What’s weird though is the cabin doesn’t smell when I first fill it up, it’s when the car sits parked for a couple hours after the fact. Could it be a fuel leak or clogged charcoal canister? Or worst case a cracking gas tank as I know these cars so commonly have
‘83 Platinum N/A 944
I have an ‘85.5 944 with the same or similar issue.
A fuel smell in garage after the car is parked, and is really only noticeable when the tank is over maybe 40% full.
No smell in the car unless driving with the windows down, then only faintly.
No fuel staining evident on the bottom of the tank or on the ground.
I’ll follow the thread with interest to see what suggestions come forth.
A fuel smell in garage after the car is parked, and is really only noticeable when the tank is over maybe 40% full.
No smell in the car unless driving with the windows down, then only faintly.
No fuel staining evident on the bottom of the tank or on the ground.
I’ll follow the thread with interest to see what suggestions come forth.
Tim
Current:
‘85.5 944 Coupe-Alpine White/Burgundy
‘13 Boxster S-Guards Red/Tan
Former:
’83 944 Coupe
‘84 944 Coupe
’90 944S2 Cabrio
’95 968 Cabrio
’95 993 Carrera Coupe
‘01 996 Carrera 4 Cabrio
‘06 987.1 Cayman S
‘09 987.2 Boxster
Current:
‘85.5 944 Coupe-Alpine White/Burgundy
‘13 Boxster S-Guards Red/Tan
Former:
’83 944 Coupe
‘84 944 Coupe
’90 944S2 Cabrio
’95 968 Cabrio
’95 993 Carrera Coupe
‘01 996 Carrera 4 Cabrio
‘06 987.1 Cayman S
‘09 987.2 Boxster
-
Britmat
- Posts: 10
- Joined: Mon Apr 18, 2022 6:45 pm
- Location: UK
- Has thanked: 15 times
- Been thanked: 5 times
- Contact:
I also have a similar issue. Been chasing it for a while. The fuel smell is in the cabin, but also I can detect it when I’m in the garage before getting in the car. I can also pick it up while driving, with windows down.
No signs of fuel leakage anywhere in the system from the tank to the injectors, but clearly there’s a vapour leak somewhere. If I get anywhere, I will update, but I wanted to chime in, in case anyone has any suggestions or experiences to share…
No signs of fuel leakage anywhere in the system from the tank to the injectors, but clearly there’s a vapour leak somewhere. If I get anywhere, I will update, but I wanted to chime in, in case anyone has any suggestions or experiences to share…
- 1987 944 SC 3.0 … (Yeah, I made that up… sue me..! 
)
)
A failing charcoal canister is the most likely culprit, especially with the full tank issue. A small fuel leak from a line or the top of the tank is also possible. You need to get it checked; that smell is a serious safety risk.
What would be the best way to find the leak? I’ve been looking at this gas sniffer from Amazon but I don’t know how effective it would be https://www.amazon.com/Detector-PT520A- ... 213&sr=8-3
‘83 Platinum N/A 944
-
spacecad3t
- Posts: 243
- Joined: Tue Oct 14, 2025 4:54 am
- Has thanked: 63 times
- Been thanked: 52 times
I usually try to inspect the car when it's cold, as any metal is most contracted, so any metal supporting the tank or connections around the tank will be most likely to vent fumes or seep gas. Grab a tarp or something and kneel or lay around the rear of the car, the tank, pump, filter, and several rubber lines are all congregating there.
The fuel lines then run the length of the body and come out in the engine bay, along with the fuel evap system(emissions) and charcoal canister. There are cloth braided lines in the engine bay for the fuel evap system, which can vent fumes along their entire length lol... The canister itself (requires you remove the wheel and plastic liner). which can be come clogged, or in my case, I found the hose has complete broken and the fumes were not even reaching the canister.
As mentioned, the gas tank is actually fairly reachable from the trunk, lift the carpet.
To me, biggest risk and immediate inspection on ANY car, are engine bay fuel lines. Fuel injection is high pressure and every car has rubber fuel lines traversing hot engine parts. The 944 has at least 2, the feed and return lines, that cross over the engine head and in some cases the exhaust headers, lol?
I recommend checking all of your fuel lines, specially the engine bay ones, and if you have original feed/return lines, buy a nice replacement kit. I recommend one with extra hose so you can route the lines around the head (photo attached).
I dont want to come off making product recommendations, but "cough" rennline "cough" sells a nice long kit.
The fuel lines then run the length of the body and come out in the engine bay, along with the fuel evap system(emissions) and charcoal canister. There are cloth braided lines in the engine bay for the fuel evap system, which can vent fumes along their entire length lol... The canister itself (requires you remove the wheel and plastic liner). which can be come clogged, or in my case, I found the hose has complete broken and the fumes were not even reaching the canister.
As mentioned, the gas tank is actually fairly reachable from the trunk, lift the carpet.
To me, biggest risk and immediate inspection on ANY car, are engine bay fuel lines. Fuel injection is high pressure and every car has rubber fuel lines traversing hot engine parts. The 944 has at least 2, the feed and return lines, that cross over the engine head and in some cases the exhaust headers, lol?
I recommend checking all of your fuel lines, specially the engine bay ones, and if you have original feed/return lines, buy a nice replacement kit. I recommend one with extra hose so you can route the lines around the head (photo attached).
I dont want to come off making product recommendations, but "cough" rennline "cough" sells a nice long kit.
- Add Pictures/Files
-
- m44_1.jpg (2.89 MiB) Viewed 658 times
If you haven’t already, I recommend pulling the cargo carpet liner back to reveal the top of the fuel tank area. Remove the insulated pad/cover for the fuel level sending unit and inspect that area for odors/damage and ensure that it’s tightly sealed.
I’ve seen the metal elbow connections for the vapor lines snap right off the top of the sending unit, which results in fuel odors in the cabin that are much more pronounced when the tank is full. The rubber lines can also become cracked and degraded there. When replacing the sending unit, a new o-ring is recommended for a proper seal.
I’ve seen the metal elbow connections for the vapor lines snap right off the top of the sending unit, which results in fuel odors in the cabin that are much more pronounced when the tank is full. The rubber lines can also become cracked and degraded there. When replacing the sending unit, a new o-ring is recommended for a proper seal.
My car has been like this for as long as I've had it. In my case, it seems to be caused by the fuel filler drain line being clogged up.
There's a drain tube right under the filler (inside the filler door) that fills up with dirt, leaves, etc. I poke a piece of wire down there to clean it out, and that always seems to take care of the smell until it clogs up again. If you try this, be careful not to pop the drain line out of the gasket that holds it in place. I don't know if this is indicative of a bigger issue, but it temporarily rectifies the problem for me.
There's a drain tube right under the filler (inside the filler door) that fills up with dirt, leaves, etc. I poke a piece of wire down there to clean it out, and that always seems to take care of the smell until it clogs up again. If you try this, be careful not to pop the drain line out of the gasket that holds it in place. I don't know if this is indicative of a bigger issue, but it temporarily rectifies the problem for me.
-
spacecad3t
- Posts: 243
- Joined: Tue Oct 14, 2025 4:54 am
- Has thanked: 63 times
- Been thanked: 52 times
Oh yeah, a clogged vent or overflow line will do that! Pull the carpet by the passenger B/C pillar to access the filler neck.Poorsche44 wrote: Mon Nov 10, 2025 4:37 am Interesting, that must be clogged on mine as well because every time I fill up on gas it floods and spills out before the gas nozzle shuts itself off.