2018 Mercedes-Benz C-Class
Problems, recalls and owner-reported issues
Engine is the leading concern among 130 owner complaints filed for this model year. This is the 15th highest complaint count among 23 C-Class model years with reports.
Of the 2018 reports, 5 involved a crash. 2 people were injured.
What owners report most often
Recalls and investigations
No safety recalls on file.
Representative owner complaints: fuel/propulsion system
9 reports, newest first. Show all
Engine, Fuel/propulsion system, Feb 3, 2025
The engine light is on with only 35000 miles. Upon using an OBD2 scanner, error code P052e positive crankcase ventilation(PCV) malfunction was detected. It's a problem that I researched and noticed a lot of people having the same issue. I was told that this can cause the car to stall or shut down? This causes serious risk and safety issues to drivers, passengers, and pedestrians. With so many complains about this problem, I believe the manufacturer and dealers should take responsibility before tragedies happen.
Fuel/propulsion system, Feb 1, 2024
Positive crankcase ventilation assembly replacement. Pollutes the environment.
Engine, Fuel/propulsion system, Jul 26, 2023
Check engine light came on. Had a diagnostic check and was told that the crankcase ventilation sensor needs to be replaced which will cost $1200.
Other or unspecified, Engine, Fuel/propulsion system, Jul 23, 2023
My c300 2018 only has 50k and suddenly the engine light is on, when I check it shows that I need the Positive Crankcase ventilation valve replaced. it cost $2300. As I know a lot of people who own Mercedes have the same problem. Three mechanics claim it on almost all C, CLA, and GLA models. Please make Mercedes recall it finally.
Fuel/propulsion system, May 25, 2023
This particular model of vehicle has a well-known and documented failure of the PCV valve (Crankcase). This has not been identified by NHTSA to date. This should be considered for a recall due to the high incident rate of the P052E error code (valve failure) as this causes reduced emission control and possible explosions within the engine due to pressure-related issues. My vehicle did not have any warnings prior to the engine light illuminating. After diagnostics, P052E was identified. Dealership told me that it needed to be replaced as it would fail and result in damage.
Engine, Fuel/propulsion system, Apr 30, 2023
The code I received is p052e from the check engine light. This can cause the car to stall out mid way through driving and cause a potential fatal accident. This is a common issue across C300 And GLC benz.
Engine, Fuel/propulsion system, Feb 21, 2023
Failed positive crankcase ventilator after 40,000 miles common problem regulating oil consumption to the engine. Causing oil burn, oil leak, inconsistent oil ventilation. Dealer is aware of the problem. Engine light is on with code P052E. Commonly reported problem for this model on the internet.
Engine, Fuel/propulsion system, Feb 21, 2023
at 67000 miles the check engine light came on and is was engine code p052e crankcase ventilation regulator valve failure. This failure will cause the ending to exhaust increased contaniments in to the air. This is a know problem by MBUSA and they have changed the part design on new vehicles , this problems comes up right after the cars warranty and they cost to repair is in excess of $2500. For this to be an emission know problem by MBUSA a recall should be issued and this problem corrected under the recall process of the NHTSA ASAP. This has been reported to MBUSA and they have been zero help in this matter. The NHTSA is here to protect our citizens and environment and hopefully you will continue to do so.
Power train, Engine, Fuel/propulsion system, Jan 4, 2022
CYLINDER 1 SPARK PLUGS IS DAMAGED DUE TO PISTON DAMAGE, HOLE IN PISTON. IF EXTRA DAMAGE IS FOUND ON TEAR DOWN, COMPLETE ENGINE REPLACEMENT. This is direct from the repair facilities reports. While driving my 2018 C-300 there was smoking out of tail pipe, a rough vibration, hard to control the vehicle and it was starting to lose power. Not a good situation, had to pull over and have vehicle towed to the dealership. Worst part is this is a vehicle used to transport my 5 children to and from school and activities. My 16 year old also drives this vehicle, had he been driving this with this happening to him, the outcome could have been catastrophic. Vehicle has been inspected by 2 facilities; first was a certified Mercedes Benz repair facility and the second was the service dept. of the Mercedes Benz dealership I have serviced at for over 10 years. Mercedes refuses to cover repair costs or even acknowledge the major vehicle malfunction and safety issue this presents. , which is in my view ridiculous as cracked piston is not something that normally happens as the result of normal wear and tear, especially in a 3 year old luxury car. I have read several blogs on this same issue, Mercedesworld.org with over 400K members, reddit.com, benzworld.org, metrisforum.org, and numerous others. Please review these there are numerous people dealing with this and Mercedes is refusing to acknowledge. In addition, our Mercedes Benz service rep said these pistons were changed out in the 2019 model and newer due to these issues, he said he continues to see this issue with these models and advised Mercedes is well aware.