46 complaints reported

2015 Mercedes-Benz C-Class FUEL/PROPULSION SYSTEM

Owner-reported problems and safety issues filed with NHTSA. Review common failures, severity levels, and complaint trends over time.

Reports
46
Crashes
0
Fires
0
Injuries
0

Complaint Timeline

Chronological view of owner reports

Jan 2026

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.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C200, Manufacturer: Mercedes-Benz USA, LLC
Incident: Mar 2026
Jan 2026

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.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C200, Manufacturer: Mercedes-Benz USA, LLC
Incident: Nov 2026
Dec 2025

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.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Feb 2025
Jan 2025

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

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2016
Jan 2025

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)

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2024
Oct 2024

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.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Sep 2024
Apr 2024

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.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Feb 2023
Dec 2023

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

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jun 2023
Oct 2023

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

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Oct 2021
Feb 2023

The car smell like gasoline inside, the gas hose connecting the high pressure gas line to the gas tank is licking due a bad connectors

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Nov 2019
Jan 2023

Strong Gas Smell when heater comes on. Could be hazardous due to breathing in Fuel Fumes

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2023
Oct 2022

Positive crankcase ventilation valve. Known issue with manufacturer

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2022
Oct 2022

Looks like I am not the first one to complain about the strong smell of fuel on the driver side under the hood as well as inside of the vehicle. Upon further inspection it was determined that the fuel line at the pump is leaking fuel. My car has only 48k miles on it...How can such dangerous failure be ignored by MB for more than three-four years or longer?? Please note that this particular issie is leading the complaints chart. Based on the amount of identical complaints, it appears that this "manufacturer" is waiting for an injury or fatality before they do something about it. This fuel hose situation MUST be addressed IMIDIATELY. Please start the recall before it is too late!!!

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Oct 2022
Aug 2022

Strong odor of fuel in the cabin when entering the cabin and stronger when vehicle is first started

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2022
Jul 2022

Check engine lite with code P052E that is "Positive Crank Case Ventilation Regulation Valve Performance" at around 65K miles. This might pose danger with engine failure. the problem has been confirmed by an independent service center. Dealer said that this problem is common to the year and model of my car and that the manufacturer has replaced this piece in newer models. Since the manufacturer already know this issue and replaced the piece with a better one for newer model. I believe this part should be recalled and replaced by the manufacturer. it is crazy amount of money for the consumer to fix this.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jun 2022
Apr 2022

2015 C 300 Mercedes Benz Crankcase ventilation/ oil separator is bad. Vehicle has only 50,000 miles. Please help, Mercedes should have this on recall, a lot of people has this same issue. Thanks

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2022
Mar 2022

Got error code P052E when performing state inspection for my car. This looks like "Positive Crankcase Ventilation Regulator Valve" issue and have seen lot of people who owns Mercedes Benz reported this issue.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Mar 2022
Mar 2022

ONLY HAVE 35,000 MILES AND RECEIVED POSITIVE CRANK CASE VALVE

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Nov 2022
Jan 2022

When I got my Mercedes 2.5 years ago I would always notice a very strong gas smell that would come very randomly. I would have to open my windows for the smell of fuel to go away. I presented this to the Greenway Mercedes Dealership 2X VERBALLY and they told me that it is just a "Mercedes thing" and everything is ok because it is not "VISIBILLY" leaking fuel. Which it was not. However, the smell of the fuel is EXTREME, It would happen to me through out the year (in the summer and winter, regardless of temperature) randomlly. I would have to leave the garage ASAP when I turn on my car just in case the smell of fuel was extreme because my parents would tell me that it would even COME INTO THE HOUSE. I thought I was crazy to think this was normal and just a "Mercedes thing". But then I got a letter on August 2021 and did some research and saw I was not the only one and there is a class action lawsuit -Mercedes sent a letter on August 21 announcing they will extended the limited warranty of the "Fuel hose connected to high pressure fuel pump" from the original warranty of 4 years/50,000 miles to 10 years/120,000 miles. HOWEVER, This does NOT HELP, they are still saying it is a wear and tear and REFUSE to replace the defected MANUFACTORER part and INSIST it is not "seeping fuel" from the connection at the fuel pump, so it is NOT under warranty. I am confused as to why this is not a recall? Extending the warranty did nothing to help Mercedes Owners at all. They continued to claim it is "wear and tear so that is why the fuel is sweeping at a different location" AS WELL, two dealerships told me it would take them 24-48 hours for them to JUST INSPECT my car to see if it is covered. This extension did resolve anything, but made sure the dealerships deny even more. Now, I have to continue to leave my garage within 30 sec. so I don't suffocate the cats that sleep in the garage or have my family smell the fuel as I leave. And to open my windows so I can breath fresh air.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Feb 2019
Dec 2021

Constant fuel smell coming from the engine, you can see gas coming out of the high pressure line. When I park in the garage the whole house smells like gas. Even while driving gas smell coming through the vents constantly

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: May 2021
Sep 2021

Heavy fuel/gasoline smell around engine bay began approximately 2 years ago while the car was still under original 5 year warranty. Fuel smell would persist outside of the vehicle despite the vehicle not being driven for multiple days. When driven, fuel smell would permeate into the cabin of the vehicle and cause mild headaches to the occupants. Taken to dealer to find cause of smell and was advised that there was nothing wrong with the vehicle. Fuel smell continues to persist since it was originally noticed without change and vehicle is no longer within warranty period. Recently, this vehicle was taken back to the same dealer for servicing for an unrelated issue. Told the service representative that there was a fuel smell that continues to linger around the vehicle when parked and inside the cabin. This inspection revealed leaks from two fuel lines and technician recommended replacement. Warning lamps, messages, or other indicators from the car never appeared.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2019
Aug 2021

INTERMITTENT FUEL LEAK. REAL BAD GAS SMELL IN CABIN COMING THROUGH THE VENTS. DRIVER SIDE, IN BACK, DOWN BETWEEN THE ENGINE AND BODY. THE FUEL LINES ARE PRESSURIZED, SO IT MIGHT ONLY LEAK WHEN THE PRESSURE BUILDS UP. I KEPT GETTING A STRONG GAS SMELL THE GARAGE AFTER PARKING FOR LONG PERIODS.

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Feb 2020
Mar 2021

GAS LEAK/ SMELL IN CABIN AT IDLE

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Feb 2021
Jan 2021

THERE IS A FUEL HOSE (PARTS NUMBER: 274 070 3500) CONNECT TO THE HIGH PRESSURE PUMP IN FRONT ENGINE AREA. THE FUEL HOSE WAS FASTENED BY A CLAMP (NOT SURE THE PARTS NUMBER) . BECAUSE OF THE DESIGN FLAW, THIS CLAMP WILL LOOSE SINCE IT'S A SNAP JOINT ASSEMBLIES NOT TIGHTEN BY SCREWS. UNDER THIS SITUATION, THE FUEL HOSE WILL LOOSE AND AFFECTED BY THERMAL EXPANSION, THIS PROBLEM WILL CAUSE FUEL LEAK/SEEPING. WE CAN SMELL FUEL NEAR THE PUMP BEFORE WE START CAR IN COLD IN THE MORNING AND THIS SMELL CAN BE SMELLED UNTIL THE ENGINE WORKING INTO THE NORMAL OPERATING TEMPERATURE OR WHEN WE TURN ON THE AC OR HEATER . FUEL IS A VERY CRITICAL SAFETY PROBLEM AND USUALLY WE CANNOT TAKE NOTICE OF THIS POTENTIAL PROBLEM.THIS IS BEEN HAPPENING SINCE 11/19/2019 THE DATE WHEN I BOUGHT THE CAR TILL NOW

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Oct 2019
Jan 2021

Hi so i woke up this morning and my started my car as usual then noticed the smell of gas all around the car Inside and out. I got worried turned off the car and started sniffing around to see if i can find where the leak was and found out the high pressure fuel pump was leaking i looked up info on this part and it is very common on these car for that part to fail. Im very upset that there is no recall yet when the dealership told me that they do 2-3 of those jobs a week (HIGH PRESSURE FUEL PUMP REPAIRS) and still no recalls on this,what is it going to take to get one?, my car has to blow up to get your guys attention?? Oh wait other Mercedes c300 cars in the united states already caught on fire please fix this saftey hazard i want to feel safe and not worry about catching on fire. ITS BEEN 6 years AND STILL HAVE NO RECALLS FOR THIS CAR ???

Type: Vehicle, Vehicle: 2015 MERCEDES-BENZ C300, Manufacturer: Mercedes-Benz USA, LLC
Incident: Jan 2021

Trend Over Time

Complaints by year

Quick Summary

The 2015 Mercedes-Benz C-Class has 46 FUEL/PROPULSION SYSTEM complaints on file. Review the timeline above for detailed owner experiences.