Strong Fuel Smell in Cabin – Need Help!
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Strong Fuel Smell in Cabin – Need Help!
Hi everyone,
I own a 2018 Mercedes-AMG C63S and recently had a check engine light pop up for misfire on cylinder four I ended up changing all the spark plugs. I ordered off FCP euro and I also changed out the coil pack for cylinder four with a brand new one check engine light went away and now the car drives smooth and there’s no check engine light but I started experiencing a strong fuel smell inside the cabin. It’s noticeable especially after driving for a bit as soon as the car fully warms up and I have the heat on whether it’s on setting one or setting seven there’s a strong smell of fuel coming from the vents soon as I turn off the heat it obviously no longer smells like fuel in the cabin. Did I do something wrong? What do you think this is? I do not know what to do. It’s driving me nuts I might have to get it diagnosed but I really tried avoiding that I might even trade out of it to be honest. The vehicle also has 78,000 miles on it. No other issues though.
Has anyone else experienced something similar? What are the most common causes for this in the C63S or AMG models? Any tips on what to check or look for before I take it to the shop?
Thanks in advance for your insights!
Let me know if you’d like to add more details!
I own a 2018 Mercedes-AMG C63S and recently had a check engine light pop up for misfire on cylinder four I ended up changing all the spark plugs. I ordered off FCP euro and I also changed out the coil pack for cylinder four with a brand new one check engine light went away and now the car drives smooth and there’s no check engine light but I started experiencing a strong fuel smell inside the cabin. It’s noticeable especially after driving for a bit as soon as the car fully warms up and I have the heat on whether it’s on setting one or setting seven there’s a strong smell of fuel coming from the vents soon as I turn off the heat it obviously no longer smells like fuel in the cabin. Did I do something wrong? What do you think this is? I do not know what to do. It’s driving me nuts I might have to get it diagnosed but I really tried avoiding that I might even trade out of it to be honest. The vehicle also has 78,000 miles on it. No other issues though.
Has anyone else experienced something similar? What are the most common causes for this in the C63S or AMG models? Any tips on what to check or look for before I take it to the shop?
Thanks in advance for your insights!
Let me know if you’d like to add more details!
Out Of Control!!
Joined: Nov 2018
Posts: 11,469
Likes: 5,357
From: San Francisco Bay Area
2019 C63CS
If you smell fuel then you likely have a leak somewhere in the fuel system. First thing is to locate where exactly it's coming from. When the car is parked, do you smell it in the rear or in the engine bay. If the latter, then you might have nicked a fuel line or damaged an injector while doing this work. Other sources of leaks could be a fuel pump, EVAP system such as the charcoal canister, fuel sending unit or fuel filter. There are multiple parts to the fuel system, so you'll have to trace the leak.
Sometimes it could also be something rather silly. Not too long ago my wife's car reeked of fuel and the garage after parking it. Came from the passenger side rear wheel and coincided with me filling it up at the local gas station just moments before it started to smell. First I thought it could be the charcoal canister or the fuel cap leaking or something near the tank. Left the car out on the driveway for two days and the smell went away. Then I remembered there was a strong gas smell near the pump where I filled, so somebody likely spilled gas and I drove through it, so the gas was on the tire and in the rear wheel well and eventually evaporated in the sun.
Sometimes it could also be something rather silly. Not too long ago my wife's car reeked of fuel and the garage after parking it. Came from the passenger side rear wheel and coincided with me filling it up at the local gas station just moments before it started to smell. First I thought it could be the charcoal canister or the fuel cap leaking or something near the tank. Left the car out on the driveway for two days and the smell went away. Then I remembered there was a strong gas smell near the pump where I filled, so somebody likely spilled gas and I drove through it, so the gas was on the tire and in the rear wheel well and eventually evaporated in the sun.
