coaltec

I have a 2016 GLC 300 with about 55,000 miles on it. We are getting an intermittent fuel smell inside the cabin. It usually shortly after the car is started. I don’t see any evidence of the leak. Is anyone experiencing this problem or know any solutions.

chassis

Can it be related to the evaporative system? Do you have a check engine light illuminated? Can you read codes, ideally with Xentry/DAS?

p.s. You posted about a GLC300, this is the GL section of the site. There is a GLC section, where if you post the question there, it will probably receive faster replies.

coaltec

Thanks for the response. There is no check engine light or error code. That would certainly make this an easier problem to solve. I will repost in the correct section

Stephan Eff

Did you ever find a solution for this problem? I’m currently experiencing the exact same thing!

ItalianJoe1

There was a bulletin applying to the 205 chassis with the M274 for the rubber part of the fuel feed line in the back of the engine bay leaking/seeping and causing a fuel smell. I'd check there. The line is easily accessible from under the car, runs from the test port in the line to the high pressure fuel pump on the back of the engine. The bulletin was just to replace the line and clamps, I'm unsure if the part actually changed or they just had a bad batch.

coaltec

Yes I did and I should have posted it. The amperage on the battery had dropped due to age. It would still start the car, but it was making the computer discharge the fuel smell. It instantly went away with a new battery. We have made the same suggestion to others and it worked. The MB dealers and local mechanics were all useless. I ended up figured this out myself!

Stephan Eff

The smell occurs only on cold mornings, starts within the first 15 minutes of the car being on and it does not last more than 2 minutes. No leaks, no engine lights

coaltec

That is pretty much the same issue we had. Take your battery to a shop or store and check if the amperage is below spec. Low amperage was causing the issue. Battery performance is impacted by cold weather. ;

Jetfuture

49,500 miles...we've been getting an intermittent gasoline odor as well on our 2016. Wife drove into garage tonight and the entire garage reeked of gasoline. Did all the normal checks with engine running, no leaks found. I do believe our battery amps are a bit low, as the run-stop engine has not stopped in about 6 months. No DTC's or any other issues.

chassis

Sounds like it's time for a new battery.

Jetfuture

I agree. Tested fine at 40,000 miles and getting close to 50,000 now.

Going to just replace it this week before winter hits in earnest. Battery is coming up on 5 years old.

More importantly, what could a low battery have to do with a gasoline odor? Is there something in the fuel or evap system which requires a stronger battery? Never heard of this.

tisi_03

Just had this problem about a month ago. It would throw a CEL though. They tried the gas cap first, then the evaporator canister and then finally did a smoke test and found the problem to be a leak in the tank where one of the fittings attached on top. I'd smell gas in the garage but not in the GLC. It would throw an intermittent CEL depending on how full the tank was, based on whether it could pressurize properly or not. They ended up replacing the fuel tank which is right under the back seat, problem solved.

Jetfuture

Hmm....seem to be slightly different symptoms. No CEL, we get odor inside car, and odor happens whether fuel is at 1/8 or at 8/8. Thanks for the response. I hope it is not a fuel tank, as just the part alone is $1,000 before we get into diagnostics, labor, trying cheaper fixes first, etc.

Jetfuture

Found the leak. There is a couple droplets of fuel on the lower part of the U-shaped fuel line transition hose that connects the two hard lines. Not enough to drip on the ground, but certainly enough to cause the entire garage to stink like gasoline. It's on the bottom of the car and you can see the hose up above the protective underbelly plastic. Looks like the 2016-2017 Metris vans had a recall for this exact problem. Our car is out of warranty by 6 months, so will be on the hook for this. Looks as though the clamp on one end was not applied properly (and that is exactly what the Metris recall stated was the problem - the clamp).

ajmtbm

wont hurt to try with the dealer - given its a gasoline leak they may be inclined to consider it a warranty repair, especially since you are not that far out of warranty

ItalianJoe1

The line going to the engine that I mentioned?

Jetfuture

Yes. Dealer replaced that rubber transition hose and the fuel line going from that and up to the engine - $355 or so. Looks like a common problem. Also, replaced the battery and the run stop started magically working again after not working all year.

Thanks Joe

ParjAS

2016 problem or all years?

Potomacster

Hi Jetfuture, can you tell me which dealer you had this done with? Mine wants 750.00 to fix at Euromotorcars. Thank you for posting. John

Jetfuture

Brian Bemis Mercedes in Sycamore, IL.

sdwingnut

That's interesting, I have a 2017 GLC300 with 55,000 miles and a strong gas smell in the cabin. It was mild for the last week or so, I replaced the battery (it was down to <12.5V anyway) and the smell *got worse*. Now, it could be because of the weather (it's colder the last few days and we tend to have the blower fan on a higher setting), but it definitely didn't go away with a new battery. Seems to be a different root cause.

hmj

Our GLC has approx 62k miles and we intermittently get fuel smell when starting car. There are no apparent fuel leaks. What can we do?

sdwingnut

Take it to your dealer, there is a fuel line recall. It fixed the gas smell problem we had immediately.

jtmann

I have a 2017 GLC300 4matic, and this recall does not appear for my vehicle. All recalls have been performed, yet I still get the fuel smell. Any other ideas? I did have a p052e code the mechanic reset after changing out a "leaking" fuel injector. $900 later still no fix. The code did not return but the fuel smell issue was not resolved.