2012 Mercedes-Benz CLS550 Fuel system Problems
- Complaints
- 8about this part
- Share
- 35%of 23 total for the year
- Median mileage
- 81,000miles
- Trend
- Not enough dataFewer than 15 complaints, too few for a reliable trend.
NHTSA recorded 8 complaints about the fuel system of the 2012 Mercedes-Benz CLS550, 35% of the 23 complaints for this model year. Where a mileage was given, the median is 81,000 miles.
Fewer than 15 complaints name this part, so treat the figures as a rough indication only.
Example complaints
Selected from NHTSA records; personal details are removed. They are consumer reports, not findings.
“Fuel leaking from gas tank after smelling a strong fuel smell both inside and out side my vehicle I took to mercedes 9/17/18 to see if they knew of the issue of if there was some type or recall on my vehicle regarding a fuel issue. The smell always seemed stronger after I put in a full tank of gas. They did a visual inspection and told me they see fuel leaking from my vehicle and that there was no fuel related recall. They wanted to charge me $185 just to see what the actual problem was and didn't really have a concern if the vehicle was safe to drive or not. …”
NHTSA complaint #11130069, filed 2018-09, 81,000 miles“For several months I been smelling different odors from my 2012 CLS550, getting stronger as the weeks go by now smelling like gas, would noticed puddles whenever I parked from rear driver side area towards middle, just got the news from the mechanic that the driver side fuel gas pump is cracked and leaking gas and passenger side is also cracked. Labor + parts $1,660.00..”
NHTSA complaint #11691178, filed 2025-10“I have Mercedes Benz CLS 550. Whenever I fill up a tank full, I smell gas in the CAR and in my garage. After researching the cause of this issue , I found its a common issue with Mercedes Benz older vehicles where the fuel sender unit cracks and start leaking Gas which is located under the rear seat driver side. Mercedes Benz sent a recall notice for same problem for older vehicles from 2006-2008 to fix this issue. Below are the steps to reproduce the issue 1. Fill the car up. 2. Drive straight home. 3. Park in the driveway. 4. …”
NHTSA complaint #11649224, filed 2025-03“Fuel leak into rear driver side back seat from below. Gas leaked into passenger cabin due to a seal that broke from gas tank. Dangerous smell and fire hazard. Leak happens all the time, when parked and especially when driving. Mbusa and dealerships not accepting the defect and design flaw that causes gas to sputter into passenger cabin when driving.”
NHTSA complaint #11360481, filed 2020-09“There is a strong odor of gasoline coming from the drivers side rear. I conducted a Google search on the issue and there are a lot of instances of the same thing. It appears to be the Gas Tank Sending Unit, they have a tendency to crack and leak.”
NHTSA complaint #11676483, filed 2025-07Related service bulletins
- 10167487Mar 21, 2014Minor leaks at the oil duct of the left or right cylinder head of engines 157, 276 and 278. 1. Left cylinder head: Oil passage plug hole on left beside mechanical vacuum pump. 2…
Fuel system: other model years
Other parts of the 2012 Mercedes-Benz CLS550
4 complaintsBrakes
3 complaintsElectrical system
3 complaintsOther or unknown
3 complaintsTransmission and drivetrain
3 complaintsSteering
2 complaintsSuspension
2 complaintsVisibility (wipers, defrost, mirrors)
2 complaintsWheels
1 complaints
← All problems reported for the 2012 Mercedes-Benz CLS550
About this data. Data from NHTSA (ODI) complaints, recalls, TSBs and investigations, updated Oct 31, 2026. Complaints are unverified consumer reports and may be duplicated or inaccurate.
To check a specific vehicle for open recalls, use its VIN at nhtsa.gov/recalls. Methodology