10.0

really awful
Crashes / Fires:
0 / 1
Injuries / Deaths:
0 / 0
Average Mileage:
13,307 miles

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« Read the previous 20 complaints

problem #79

Mar 012023

C300

  • 90,449 miles
The contact owns a 2015 Mercedes-Benz C300. The contact stated that while driving at an undisclosed speed, the vehicle hesitated and stalled. The check engine warning light was illuminated. The vehicle was towed to Safety Auto Repair where it was diagnosed that the engine failed and needed to be replaced. The vehicle was not repaired. Neither the dealer nor the manufacturer was notified of the failure. The failure mileage was approximately 90,449.

- San Bernardino, CA, USA

problem #78

Jan 302023

C300 4-cyl

  • miles
Driving the 2015 c300 with approx. 69k in miles down the highway and heard a pop and the check engine light came on. The next day there was a rough idle and clanging at low speeds. took to dealership and they quoted me $15k in repairs for a new engine. MB tech said the cylinder #1 is out of spec., and there is scoring on cylinder wall caused by the piston being off center and riding the cylinder wall. After doing research this is a common problem with the m274 engine. How has this not been recalled and taken care of by Mercedes?? At this point i am 'forced' to either come up with $15k for the repairs, or go to MB dealership and try to get into a new car...which i am over $12k upside down on i might add

- Phoenix, AZ, USA

problem #77

Feb 152023

C300

  • miles
Check engine light came on and strong fuel smell. Crankcase ventilation malfunction code was verified by dealer.

- Denton, TX, USA

problem #76

Feb 152023

C300

  • miles
When driving I accelerated and then the engine light turned on. after that the car was jolty and turned off completely when stopped. had to force a restart at the light. code that came back was p052E. This is a major and common issue with these cars. part is 400+ dollars. labor is much more since this is a 6 hour job. the work to replace this part is incredibly intensive that makes it impossible for regular car owners to change. Mercedes refuses to recognizes this as a common issue. but the truth is they designed a faulty system that they claim to have updated a handful of times now.

- Chicago, IL, USA

problem #75

Feb 012023

C300

  • miles
P052e71 positive crankcase ventilation regularly valve issue. This is a common issue Mercedes is aware of with their vehicles. I was quoted 1600+ for a repair for something has been known about for over 7 years to be an issue with the car class. I was also told by the shop that this a very common issue and odds are I would need the same service within a year or two.

- Fairview Park, OH, USA

problem #74

Feb 132023

C300

  • miles
My check engine light was on when I was driving on the highway. I was terrified that something was very wrong. Right after, I took the car to the dealer and was told that the valve for the crankcase ventilation. The actuator was blocked. I was also told that this is not caused by something I did. It's the design of the car that caused the problem.

- State College, PA, USA

problem #73

Jan 162023

C300

  • miles
Oil separator failure. This a common design fault as documented by multiple complaints on the internet. This is another Mercedes Benz emission design flaw causing emission failures. This is very cheap part but extremely expensive to replace. Mercedes collects over $1200 per labor repair for each. THIS IS AN EMISSIONS POLLUTION AND SAFETY ISSUE THAT CAN BE SOLVED. PLEASE FORCE A RECALL. Engine severely smokes/stalls leaving people stranded on highways. When stuck, coolant is sucked into the engine mixing with the oil. No warning. The car

- Lake Placid, NY, USA

problem #72

Nov 262022

C300

  • miles
I have 2015 C300 Model, total milage on the car is 30K. Dashboard is showing the check engine light and when I take to Dealership for diagnostic, the code is P052E which is a problem with Crankcase vent. Dealership tech had mentioned that this seems to be known issue effecting years 2015-2018. When I did search, he is right; many MB owners are facing same issue which is a malfunction during assembly/manufacturing. MB should be responsible for part replacement and labor. Please investigate and ask MB to run recall campaign. Thank You.

- Danbury, CT, USA

problem #71

Dec 012022

C300

  • miles
Vehicle experienced loss of power and rough running when check engine light came on. Mercedes dealer reported one of the pistons cracked resulting in catastrophic engine failure with just shy of 61,880 miles on it.

- Virginia Beach, VA, USA

problem #70

Jan 062023

C300

  • miles
These cars have a known wrist pin failure, mercedes refuses to cover the cost of repairs as its not a recall. My vehicle is the specific model and year this is known for, and my car is making these piston slapping sounds, worse everyday. Worse on deceleration, goes away when warmed up, just like the reports. I am afraid I'll lose power while driving and hurt myself or others.

- West Chester, PA, USA

problem #69

Jan 042023

C300

  • miles
It cuts out randomly while pressing the gas pedel to get out of the way of traffic and cuts out and stalls ive had it looked at and they say theres no check engine codes and that they cant make it do it. Theres many of people with the same issue online and the dealers wont help them either

- Sparks, NV, USA

problem #68

Dec 212022

C300

  • miles
I have an emissions related Check Engine Light (P052E71) relating to the Evaporative/Crankcase ventilation system. I think this should be a Recalled/Warrantee item on the 10 year/100,000 miles federally mandated guarantee. Please advise...

- Northport, NY, USA

problem #67

Oct 012022

C300

  • miles
Common problem mercedes hasn-??t addressed from the factory crankcase breather element at less than 50,000 miles and the smell pf gas that comes in to the cabin is horrible

- Gaithersburg, MD, USA

problem #66

Dec 272022

C300

  • miles
The dealership is staying I have an issue with the crankcase valve vent and this seems to be a known issue effecting years 2015-2018.

- Bowie , MD, USA

problem #65

Dec 222022

C300

  • miles
2015 Mercedes C300 crankcase ventilation regularly valve is garbage, have to spend around $2K to get it replaced. Very common issue for this model.

- Portland , OR, USA

problem #64

Dec 072022

C300

  • miles
Car is at 60,000 Miles and code for Positive crankcase ventilation appeared. Why does this happen to a trouble free car after warranty runs out"????????" Seems like hundreds of complaints all over the internet and Dealer charging big money to fix their design Flaws.

- Macomb, MI, USA

problem #63

Oct 012022

C300

  • miles
Crankcase (pcv) problem of the 2015 Mercedes Benz C300 Diagnosis code p052e pcv regulator valve replacement/crankcase replacement. The code keeps coming back with check engine light on dashboard. To replace part, the engine has to be taken down since the crankcase is inside the engine. This is a malfunction during assembly/manufacturing, it is impossible to damage part while under usage. Mercedes benz should be held responsible for part replacement and labor. This is a common defect and should be recalled.

- Plano, TX, USA

problem #62

Nov 092022

C300

  • miles
Crankcase Ventilation Regulator Valve

- Highlands Ranch, CO, USA

problem #61

May 012022

C300

  • miles
This occurred after an oil change. it is the P052E code crankcase ventilation code.

- West Hartford, CT, USA

problem #60

Nov 092022

C300

  • miles
CEL light- with code P052e positive crankcase ventilation regularly valve.

- Chattanooga, TN, USA

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