There are 3 owner-reported engine complaints for the 2013 Mercedes-Benz SL-Classin NHTSA's database. These are unverified consumer reports and may not reflect confirmed defects.
I was driving on a country road when all of a sudden my car lost power all the warning lights camo on the dashboard. Smoke started billowing out from the back and front of the car. It turned off and I only coasted about a 100 feet. I could not safely pull off to the side of the road as the car had no power. Thankfully the road was not very busy and the tow truck collected the vehicle. Upon further inspection I saw a lot of oil on the road and the mechanics were able to confirm that the engine block was cracked and there were 2 large holes. Upon further research I was able to find a lot of similar cases with this specific M278 Mercedes engine and premature failures that happen because of bad cylinder coating. In later engines they update the cylinder lining to a more durable steel sleeves. I think this is a very well documted issue and a huge safety risk. There is a class action lawsuit running about the M278 engine and I think you need to get involved and hold Mercedes accountable for their poor design.
Cam sensor seals failed which leaked oil into the wire harness, O2 sensors, and ECM. This happens to be a common problem with M278 engine. The repair was $10,217 to fix this issue. The car would not pass emissions without this repair. Could oil into the electrical system pose a fire hazzard?
MY VEHICLE HAS A CAM SEAL LEAK THAT LEAKED OIL INTO THE WIRING HARNESS AND WIRING HARNESS AND OTHER COMPONENTS NEED TO BE REPLACED -- THE BILL IS $10,800 --- THIS CAM SEAL WAS A RECALL ISSUE FOR THE C CLASS AND FROM WHAT I READ SEEMS TO BE THE SAME OR SIMILAR ISSUE --- NOT AN ORDINARY WEAR AND TEAR ISSUE - THIS IS SHOULD BE A RECALL ISSUE AND MERCEDES SHOULD FIX -- THE CHECK ENGINE LIGHT CAME IN AND THEY SAID ENGINE WOULD NOT HAVE STARTED AND I WOULD HAVE BEEN STRANDED -- IT IS CURRENTLY BEING FIXED AT THE DEALER AT MY EXPENSE
Complaints are unverified consumer reports submitted to NHTSA. A high complaint count may reflect vehicle popularity, not defect severity. Data sourced from NHTSA public records.
Data synced from NHTSA on Apr 26, 2026