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Getting a strong gas smell every morning when I start it for about 2 months (persistently got worse). The other day I went to fill it up and gas started leaking out from under the car.
Took it to the dealer (Mercedes of Clearwater) and as always, they cant find anything. They did the fuel line campaign a couple years ago and said it cant be that. They said they do not see a leak and I assured them I watched it leaking.
Has this happened to anyone? Thanks in advance!
Last edited by Robb92914; Jun 4, 2025 at 01:54 PM.
Bad gas cap?
Gas cap has an overflow. Not likely leaking, but easy to check at least.
Something else that is back there probably the evap canister. Usually fuel doesn't go in there though.
Best might just be get some ramps and reverse up. Or maybe an inspection camera and peak under the car.
Lots of hoses running back there, but then the dealer said they couldn't find it.
Thats a big leak.
Last edited by waterzap99; Jun 4, 2025 at 03:28 PM.
Can someone remind me what the "fuel line campaign" was about ... was it something about a leaking fuel line under the rear seat (smell inside the car) or something different?
it sounds familiar but now that I have an S560 would like to refresh my memory ...
The one that comes to mind is fuel leaking in the valley of the engine due to heat aging of rubber hose.
Recall was revised to add silver heat shield as initial revision of material did not solve issue.
The gas leaking while filling the tank is something commonly associated with a failed seal at the fuel pump. The pump can be accessed under the rear seats. I've had this on my W221 and W212, but replaced the fuel pump on my W222 when I got the car due to mileage.
The easiest way to confirm is to remove the rear seat bench (or right side rear seat if you have reclining rear seats) and check the top of the fuel tank for leaks.
Recently had a code P0456 (EVAP small leak) on my 2011 C350, YouTubers showed leaks found at fuel filter and pump access cap on C class, E class, S class, CL class, and ML class vehicles.
My access cap was wet so replaced and topped off fuel, next morning fuel filter was now wet so replaced.
On both parts it looked like fuel had seeped through electrical pins when tank was full.
It’s been a couple months no further issues.
Can someone remind me what the "fuel line campaign" was about ... was it something about a leaking fuel line under the rear seat (smell inside the car) or something different?
it sounds familiar but now that I have an S560 would like to refresh my memory ...
Thanks, very interesting ... I'm guessing if that line has the insulation covering - either from this svc campaign or as built in the factory - then you're ok. What was the failure symptom for this? A smell of gas from the leakage onto the engine?
Last edited by Tom in Austin; Jun 5, 2025 at 06:41 PM.
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