What 433 owners told NHTSA about the 2015 Mercedes-benz C-class Phev

I was driving my car was sputtering or trying to shut off while I press the gas and I let go of the gas and it catches and stayed on. I took it to the dealership and they said they found nothing wrong. May 3rd around 12pm im driving on the freeway and as im getting on the express lane going 60 it dies and I couldn't move the steering wheel and I slammed into a guardrail. After doing research my car (vin [XXX] ) had multiple recals from the fuel pump and steering wheel and the dealership never fixed or checked any recalls before selling it to me. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11736219

Fuel pressure pump hose on top of the engine leaks gasoline this is a serious safety concern the hot engine can catch fire easily, I noticed due intoxicating vapors in cabin while driving because car takes air from q side of the engine to the cabin. The car only has 28k miles on it.

NHTSA ODI 11721304

After strong fuel odor in interior of car, inspected the engine and discovered fuel in the top of the engine this is a serious safety concern due possible car fire. The leak appear to be due failure of a top engine gasoline hose due low quality. The car barely has 30k miles .

NHTSA ODI 11720037

1. What component or system failed or malfunctioned? The low-pressure fuel feed line (Part No. 274-070-35-00) and its associated clamps connected to the high-pressure fuel pump. Availability: State: The defective hose is currently on the vehicle and is available for inspection. If the repair proceeds, I request the dealership to retain the failed part for my inspection. 2. How was your safety or the safety of others put at risk? The failure resulted in raw fuel leaking directly into the engine compartment. This creates an immediate and severe fire hazard, as gasoline is being released near high-temperature engine components. Furthermore, the strong odor of gasoline entered the cabin through the HVAC vents, exposing passengers to toxic fuel vapors while the vehicle was in operation. 3. Has the problem been reproduced or confirmed? Yes. The defect was confirmed by Mercedes-Benz of Orange Park (Dealer Code: 64111). The technician performed a 'cold start' inspection and verified fuel leaking from the low-pressure line to the high-pressure pump. > Note: My service advisor's admitted: Yes sir we will do the hose. 4. Has it been inspected by the manufacturer, police, insurance, or others? Answer: The vehicle has been inspected and the failure documented by an authorized Mercedes-Benz dealership technician. It has not yet been inspected by insurance or police as no fire has occurred yet; however, the dealership has identified the part as defective. 5. Were there any warning lamps or other symptoms prior to failure? There were no warning lamps or dashboard messages. The primary symptom was a pungent smell of raw gasoline inside and outside the vehicle, specifically during cold starts. These symptoms first appeared recently [January 3rd, 2026] and became persistent as ambient temperatures dropped.

NHTSA ODI 11712884

Strong gas odor coming from vent when heat and AC is on. Odor was causing dizziness and had to drive with window open or vent off. When opening the hood gas odor was also present. Brought to the mechanic and found fuel lines leaking. Went online and found out this is a very coming problem. I had to spend $657. to repair. Mechanic stated Mercedes issued a service bulletin but not a recall.

NHTSA ODI 11712012

Fuel hose system leaking. Inhalation of gas fumes caused headaches and nausea. Risk of vehicle fire. Yes, the problem has been confirmed by a Mercedes dealer. This is a known issue with Mercedes C300 2015 models and other years. There have been other complaints/lawsuits against Mercedes not wanting to pay for the issue. No warnings just strong gas smell.

NHTSA ODI 11707032

Due to the type of fuel line and clamps used to fasten them, cold weather has caused them to shrink such that gas leaks, which comes through the car vents into the car cab and now into my [XXX] and [XXX] kids's lungs. Mercedes has issued a 10 year warranty on this specific feature, but it should be a safety recall unless we agree that inhaling gas vapors is okay for your health. INFORMATION REDACTED PURSUANT TO THE FREEDOM OF INFORMATION ACT (FOIA), 5 U.S.C. 552(B)(6)

NHTSA ODI 11638347

There seems to be a continuous gas smell in my car and I see some class action law suits for the same problem but dealership says there is no recall- synopsis of class action below February 26, 2021 — A Mercedes C300 fuel smell has led to a class action lawsuit that alleges 2015-2019 (W205) C-Class vehicles have defects that cause fuel leaks and odors. According to the Mercedes-Benz class action lawsuit, fuel can leak into the engine compartment from fuel line connections to the fuel pump at the rear of the engine compartment. Mercedes C300 and other C-Class vehicle occupants complain of strong fuel smells caused by the fuel leaks. Please assist

NHTSA ODI 11638428

Purchased vehicle in march 2024 it went thru emission inspection in 2022 after failing it passed second time . I go for inspection and it fails emission test again just passed two years later. After doing my research Positive Crankcase Ventilation System seems to be a very common problem. It also cost 2000 to fix. Appreciate you time thank you

NHTSA ODI 11607201

Unknown

NHTSA ODI 11589816

Very strong gas smell inside the car when started and heat or air is turned on. I have done research and it is a common issue with this car. This is a very serious issue that can cause an engine fire with the gas leaking in the engine compartment.

NHTSA ODI 11584382

I got my oil changed last week and not my car has the check engine light on and is throwing the code p025e. From what I’ve read this is common problem in these cars. It’s an environmental hazard, because when this happens the car is not dispelling the fumes as it should and cannot be ventilated correctly.

NHTSA ODI 11582042

My 2015 Mercedes Benz vehicle is rarely driven as I took public transportation to work and has ~55000 miles. However, the engine has started throwing error code P052E verified by an independent dealer - crankcase ventilation valve failure. It means the engine could shut off amid driving and I did research and it seems like a very common issue that Mercedes Benz car owner encounter and feels like a severe car defect.

NHTSA ODI 11568638

I have a fuel smell in the cabin of my car which started about 3 weeks ago. I have drove the car a couple of times and it was pretty bad, also my sunroof almost blew off the car while driving to dry the car after removing the salt from the streets after the snow. I have since parked it in the garage to avoid any further damage. I will submit pictures so you can see the sunroof.

NHTSA ODI 11566872

High pressure fuel line leaking, strong gas fumes smell in cabin

NHTSA ODI 11560827

Emissions Failure P052E - Positive Crankcase Ventilation Regulator Valve Performance. Vehicle has been inspected. Warning lamp appeared for my engine recently. Cause by faulty plastic valves that requires a significant costly repair - around $3,000 USD

NHTSA ODI 11558631

1. A faint smell of fuel, occasionally, external of vehicle. 2. The headlights has a water fog mist inside of headlight lens. 3. The seats and car interior cracks easily. (Seats, arm rest and dashboard) etc.

NHTSA ODI 11550450

The contact owns a 2015 Mercedes-Benz C300. The contact stated that after refueling, the contact smelled a gasoline odor throughout the interior of the vehicle. The check engine warning light was illuminated. The vehicle was taken to an independent mechanic, who diagnosed a failure with the canister purge valve. The vehicle was not repaired. After investigating the failure, the contact related it to NHTSA Campaign Number: 15V138000 (Fuel System, Gasoline), but the VIN was not included. The manufacturer was not notified of the failure. The failure mileage was 10,000.

NHTSA ODI 11548209

P052E PCV value problem Google search results show this is a very common problem, and despite being a component of the vehicle emissions system, Mercedes is refusing to repair under the emissions warranty.

NHTSA ODI 11545073

Just got my car from the mechanic on 7/21/23 and it through an error code as I drove home. Towed back snd mechanic stated I need to replace the crank case vent valve assembly. Further stated that they keep in stock because it happens often. Error code P2188

NHTSA ODI 11534426

Mercedes Benz via American Service Center in Arlington, VA regarding the service they performed on my 2015 C300 W4 4Door Sedan AWD the following issues have presented: ISSUE: 03MBZZWARN1 ENGINE LIGHT TECH: 901844 PROBLEM: ENGINE HARNESS, ENGINE CONTROL MODULE, CRANKCASE VENT VALVE, AND O2 SENSOR BANK 1 CAUSE: FOUND OIL IN THE ENGINE HARNESS AND ENGINE HARNESS. OIL IS ENTERING THREW [SIC] THE CRANK CASE VENT VALVE. RECOMMEND REPLACING. Approximate miles at the time of this issue: 63,141. Cost of Repair: $8309.58 Yes, the vehicle is available for inspection. Safety concerns: The vehicle is not able to pass an emissions test with the engine light engaged. Per America Service Center in Arlington, VA, which is the only service center that has serviced the vehicle during my ownership, they commented and documented that oil is entering through a vent valve. My additional concerns are: If an odorless fume is passing into the passenger cabin and the vehicle can not pass state emissions these are immediate concerns. The service center advices that I may continue to drive the vehicle. However, I am concerned should the oil fully empty without warning the vehicle may fail while in use on a dangerous roadway due to cause and effect of additional unknown maintenance related operational co-dependent mechanical components.

NHTSA ODI 11524033

2015 C300 Crankcase Ventilation Valve Replacement P052E71 NEED TO BE REPLACED, ENGINE LIGHT COMES ON. ONLY HAVE 37,000 MILES MANY REPORTS OF THIS ISSUE

NHTSA ODI 11514640

My son's car was blowing white smoke out of the exhaust and had a sweet burning smell and the check engine light came on. The crankcase vent valve is needing to be replaced on this 2015 C300 Mercedes Benz and many owners of this same type of car (different year) are posting about it. Owners of these types of cars are saying that replacement is happening more than once! That it's a common defect of these cars. My son has less than 100,000 miles (61,000 if that) and this shouldn't be happening. And, it's time someone does something to protect the consumer. Mercedes-Benz dealers are taking advantage of consumers and charging ridiculous prices to replace this part, but the part shouldn't be breaking. It's a safety factor in that it can affect driving, there's risk of blowing valves/valve cap and engines, including loss of the vehicle and nowadays no one can afford to buy a new car or even a used one! Consumers buy what they think is a reliable vehicle but Mercedes isn't taking care of their customers. Mercedes-Benz should be forced to do a recall and replace these faulty parts. Read other complaints here: https://www.benzworld.org/threads/2015-c300-crankcase-ventilation-valve-replacement-p052e71.3047538/page-2

NHTSA ODI 11513522

When start the engine, or idling, it smell gasoline in the cabin so bad.

NHTSA ODI 11511283

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

NHTSA ODI 11509160