RoadVitals

2018 Mercedes-Benz C 300 Engine Problems

Owner-reported complaints naming the engine system, filed with NHTSA

Data refreshed

Engine reportsComplaints are reports submitted to NHTSA by owners and drivers. NHTSA does not verify most reports before publishing them, and a complaint does not establish that a defect exists. Volume is influenced by how many of a vehicle were sold, how long it has been on the road, and how much attention an issue has received.
35
Latest Jan 9, 2026
Share of all reportsThis category as a share of every owner report on file for this model year. One report can name more than one component, so the categories overlap.
36%
of 97 total
Crash or fire reportedReports in this category whose submitter recorded that a crash or a fire occurred. The reporter's own answer on the NHTSA form, not a verified finding.
0
Injuries or deaths reportedTotals the submitters entered on their own reports in this category. Not verified by NHTSA and not a casualty statistic.
0

What this page shows

Reports naming the engine itself — including stalling, misfires, oil consumption, cooling and internal engine components. Every record below is an owner-reported complaint about the 2018 Mercedes-Benz C 300 submitted to NHTSA — not a confirmed defect, not a recall and not a manufacturer bulletin. 35 reports on file name it.

Complaints are reports submitted by owners and drivers to NHTSA. They are not verified and do not establish that a defect exists.

Owner reports naming engine

The 25 most recent of 35, in the owner's own words

Engine
Filed Jan 9, 2026

Check engine light comes on, Error Code P052E, after a lot of research, this is a known defective part by Benz. Huge safety issue not addressed by them. Very costly to fix for a customer. There is a new and improved replacement part from Benz indicating they are aware of the faulty old parts that are currently in those cars but yet they have failed to do a recall.

NHTSA ID
11709871
Incident
Jan 7, 2026
Engine
Filed Oct 23, 2025

My vehicle only had 31,000 miles and I experienced engine failure. I bought a new engine for 16, 500. 00 dollars. Mercedes Benz did nothing. I almost got in to several accidents because the engine completely stop on the interstate. Almost got hit by several cars. This is unacceptable.

NHTSA ID
11695170
Incident
May 29, 2025
EngineFuel system
Filed 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.

NHTSA ID
11640265
Incident
Jan 29, 2025
Engine
Filed Aug 2, 2024

I need the Crankcase ventilation valve replaced and have heard many complaints about this repair.

NHTSA ID
11606218
Incident
Aug 2, 2024
Engine
Filed Jul 27, 2024

The day after I purchased my c300, the engine light popped on. I went back to dealer and they said it was a recall because of a crank case (PCV). I was upset because they never said anything about it. This was April of 2024. Note:(This Dealer was not Ray Catina’s of Edison). I went to Ray Catina’s in Edison for them to inspect car and I have been calling because I was told it was a national recall and it was on back order and should be here in June. It is now almost August and I called on the 23rd of July and received a call from Ray Catena on the 24th for them to tell me that “they were told that the new plan from Mercedes is to bring my car in and they will clear code. That’s what they are told to do.” To me, this is NOT fixing the issue. I am a little aggravated because I bought my car on [XXX] and have NOT been able to feel good because not sure what ramifications will come with me driving my car with this issue. I was told that driving with this engine light on and code that it will not harm my car. They now say Mercedes was told to reset the code and that will resolve issue? I believe this is a band aid not a fix!!! I’m a little upset. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11604857
Incident
Apr 5, 2024
Engine
Filed Jun 23, 2024

P052E positive crankcase ventilation regularly valve

NHTSA ID
11595996
Incident
Jun 23, 2024
Engine
Filed May 27, 2024

Car needs an engine rebuild at 90K miles due to a cracked piston #1, a problem with a car that received regular oil change intervals and proper service should not have

NHTSA ID
11590907
Incident
May 17, 2024
Engine
Filed Mar 25, 2024

CODE'S P052W-71 & P060A-00 THESE'S CODES HAS BEEN AN ISSUE WITH MERCEDES BENZ FOR QUITE SOME TIME NOW... ITS BEEN COMPLAINTS AFTER COMPLAINTS AND MERCEDES BENZ HAS NOT TAKING OWNERSHIP OF THE ISSUE.. THIS IS DEFINATELY A RECALL PLEASE LOOK INTO THIS I CAN BE REACH AT [XXX] INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ID
11579237
Incident
Feb 1, 2024
Engine
Filed Mar 23, 2024

The Valve for crankcase ventilation has a malfunction. The actuator is blocked.

NHTSA ID
11579025
Incident
Mar 23, 2024
Engine
Filed Mar 16, 2024

Error code P052E Positive crankcase ventilation regulator valve performance

NHTSA ID
11577820
Incident
Mar 16, 2024
Engine
Filed Feb 20, 2024

I have 33,000 miles on the vehicle and the check engine light came on. The code P052e came up Positive Crankcase Ventilation Regulator Valve Performance. I’m reading that many people have the same issue but there is no recall. Is there anything that can be done?

NHTSA ID
11573044
Incident
Feb 20, 2024
Engine
Filed Feb 5, 2024

Check engine light code is positive crankcase ventilation regulator valve

NHTSA ID
11569984
Incident
Jan 28, 2024
Engine
Filed Jan 27, 2024

An Engine Code P052E (positive crankcase ventilation regulatory valve) appeared and the vehicle only has 50K on it

NHTSA ID
11568243
Incident
Jan 27, 2024
Engine
Filed Oct 20, 2023

My car was diagnosed with positive crankcase ventilation regulator valve performance failure. This should be recalled by the manufacturer because many c300 are having this very same issue.

NHTSA ID
11551029
Incident
Oct 20, 2023
Engine
Filed Oct 17, 2023

Check engine light appeared.I took it to Mercedes and they said the crankshaft was faulty. I had to repair it and it cost me about $1800.00.

NHTSA ID
11550481
Incident
Oct 17, 2023
Engine
Filed Oct 5, 2023

Engine code: P052e - the widest spread engine issue on Mercedes which fails emissions testing. Crankcase ventilator issue which leads to stalling.

NHTSA ID
11548498
Incident
Oct 4, 2023
Engine
Filed Sep 26, 2023

Positive crank case valve failure. Check engine light on. Mechanic started this was extremely common and a costly repair on lower mileage Mercedes Benz vehicles. Mercedes Benz forums also mention this is extremely common and frustrating. This happened at slightly over 50k miles on my vehicle. Error code P052e

NHTSA ID
11546676
Incident
Aug 21, 2023
Engine
Filed Aug 5, 2023

The check engine light has been coming on to indicate replacement of vent valve assembly According to the Mercedes Benz dealership. This is a commonly known problem in MB that they should replace and repair instead of charging customers $2k. My car has below 40k miles on it.

NHTSA ID
11536699
Incident
Jul 26, 2023
EngineFuel system
Filed 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.

NHTSA ID
11534679
Incident
Jul 26, 2023
EngineFuel system
Filed 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.

NHTSA ID
11533877
Incident
May 23, 2023
Engine
Filed Jun 7, 2023

Has 27000 miles out of warranty at 5 years. PCV code bad actuator. Looks like a common problem. Should be recalled.

NHTSA ID
11525844
Incident
May 1, 2023
EngineFuel system
Filed 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.

NHTSA ID
11519686
Incident
Apr 28, 2023
Engine
Filed Feb 22, 2023

Engine light P052E, This seems to be a common problem with the C300.My concern is that Mercedes Benz hasn’t address the common issue. I own the car less than a year got it from Mercedes dealership and to be honest I expect Mercedes Benz to be better than the this to it customers

NHTSA ID
11508602
Incident
Feb 22, 2023
EngineFuel system
Filed 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.

NHTSA ID
11508446
Incident
Dec 29, 2022
EngineFuel system
Filed 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.

NHTSA ID
11508445
Incident
Feb 9, 2023

Higher-selling and older vehicles accumulate more reports. Counts are not failure rates and are not directly comparable between vehicles that sold in very different numbers.

Other components reported on this vehicle

Categories with enough reports to have a page of their own

Elsewhere on this vehicle

Data sources

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