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2018 Mercedes-Benz C 300 Fuel system Problems

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

Data refreshed

Fuel system 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.
10
Latest Feb 12, 2025
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.
10%
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 fuel storage or delivery — tanks, pumps, lines, injectors and fuel leaks. 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. 10 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 fuel system

Shown in the owner’s own words, exactly as filed

Fuel system
Filed Feb 12, 2025

The contact owns a 2018 Mercedes-Benz C300. The contact stated that while the vehicle was parked inside the garage, there was a strong fuel odor inside the garage. The contact stated that there was fuel leaking from the vehicle. There were no warning lights illuminated. The local dealer was not contacted. The vehicle was not diagnosed or repaired. The manufacturer was not contacted. The failure mileage was approximately 52,300.

NHTSA ID
11642176
Incident
Oct 1, 2024
Mileage
52,300 mi
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
Fuel system
Filed Feb 1, 2024

Positive crankcase ventilation assembly replacement. Pollutes the environment.

NHTSA ID
11569234
Incident
Jan 30, 2024
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
Fuel system
Filed 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.

NHTSA ID
11523881
Incident
May 11, 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
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
EngineFuel systemPowertrain (other)
Filed 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.

NHTSA ID
11446178
Incident
Nov 29, 2021
Mileage
62,000 mi

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.

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Elsewhere on this vehicle

Data sources

Data on this page last refreshed .