Home · 2016 Mercedes-benz C-class Hybrid · Complaints

What 315 owners told NHTSA about the 2016 Mercedes-benz C-class Hybrid

These are the actual owner complaints behind this car’s reliability verdict, filed with the federal government, unedited. They’re unverified reports, not confirmed defects: read them as leads for your pre-purchase inspection, not a diagnosis.

All (315)Crash / fire / injury (16)Engine (99)Fuel system (67)Electrical system (37)Body & structure (32)Visibility & wipers (23)Transmission & drivetrain (21)Steering (17)Brakes (9)Airbags (7)Wheels (7)

99 of 315 complaints match · Engine · clear filters · page 3 of 4

Feb 10, 2023Engine

Gas smell inside the cabin. Check engine light on . Took to dealer, stated P052e code came up. Positive crankcase ventilation valve went bad. The dealer says it is a pretty common problem for this vehicle and engine. Quote came back close to $2900 for parts and labor

NHTSA ODI 11506591

Feb 10, 2023EngineFuel system

A fuel smell can be detected at idle inside the vehicle and around the engine area. A recall for some VIN's of this model in this year was enacted but not this particular model. No visible fuel moisture can be detected. A repair facility stated it might be a faulty clamp on the return fuel line. The recall was for dirt on manufacturing between the fuel injectors/fuel rail. This is a safety / emissions problem that hopefully does not lead into a fire. No warning lights are present. This started about 2 months ago

NHTSA ODI 11506631

Feb 3, 2023Engine

My check engine light came on at about 68,800 miles. The OBD code shows that I need the Positive Crankcase Ventilation valve replaced. The repair for this is approximately $2,300 and requires about six hours of shop labor, and the part costing over $425. I’ve never known a PCV replacement on any vehicle to be more than $60, with the part itself being about $10-$20. Most times, the part can be simply cleaned and replaced. This is very disappointing. Especially given that the engine design, just two years prior, would have been less than $200 for the same repair, with part costing about $60. The vehicle does not show any symptoms of the part being blocked, as indicated in the code. There is no hesitation, loss a power or decline in fuel efficiency. However, the engine light cannot be turned off until the part is replaced. I think that $2300 to replace a part on seven year old car, well under 100,000 miles is indicative of either poor design or predatory. Hopefully, something can been done to address this. Thank you!

NHTSA ODI 11505413

Jan 31, 2023Engine

Crankcase Ventilation Valve malfunction at under 50k. Check engine light is on and I took it into the shop after gas fumes were coming into the car through the ventilation system. I was informed that has been an ongoing issue with Mercedes and I was referred to fill out this document to try and kickstart a recall process. This is a problem that is very costly, and seemingly is happening to most recent models at around the 50k mark. Beyond that is is also a safety hazard as it is causing gas fumes to enter the cabin of the vehicle.

NHTSA ODI 11504641

Jan 23, 2023Engine

code P052E on 71000 miles. The crankcase vent valve replacement.

NHTSA ODI 11503241

Jan 15, 2023EngineFuel system

MY VEHICLE (2016 C-CLASS 300) HAS A STRONG GAS SMELL WHEN THE VEHICLE IS COLD AND IDLING. SEEMS LIKE IT'S COMMON PROBLEM IN W205 C300 CARS. TAKING TO THE DEALERSHIP FOR DIAGNOSTICS THERE IS A CLASS ACTION INVESTIGATION: HTTPS://WWW.SAUDERSCHELKOPF.COM/INVESTIGATIONS/AUTOMOTI VE/MERCEDES-C300-AND-GLA250- FUEL -SMELL-CLASS-ACTIONINVESTIGATION/ YOU CAN SEE MULTIPLE PEOPLE COMPLAINING ABOUT THE SAME FUEL LINES;

NHTSA ODI 11501900

Jan 5, 2023EngineFuel system

The contact owns a 2016 Mercedes-Benz C300. The contact stated he noticed an abnormal fume odor entering through the air vents of the vehicle. The contact self-diagnosed the vehicle as having a fuel leak from the fuel pump. The vehicle was not diagnosed or repaired by an independent mechanic or dealer. The manufacturer was not made aware of the failure. The failure mileage was approximately 83,000.

NHTSA ODI 11500300

Jan 4, 2023Engine

CEL on, P052e code for crankcase ventilation/PCV failure. Vehicle has about 55k miles. Extremely common failure on these vehicles at this mileage and expensive/complicated to repair. Will not pass state emissions because of this. Given extensive anecdotal evidence of the pervasiveness of this problem, recall should be issue.

NHTSA ODI 11500226

Dec 20, 2022Engine

2016 MB C300 41000 miles. Check engine light went on. Autozone code reader said p052e positive crankcase ventilationregulation value performance.

NHTSA ODI 11498245

Nov 27, 2022Engine

Cylinder 1 misfire initially, after taking it to an independent shop it was a piston 1 failure and required the small block to be replaced at 80,000 miles with a cost of $7000.

NHTSA ODI 11495006

Nov 22, 2022Engine

The crank case ventilation valve is bad. This part should be easily changed but the dealer wants over $3000. Happened at 62,000 miles.

NHTSA ODI 11494627

Nov 15, 2022Engine

(P052e) positive crankcase ventilation regularly valve

NHTSA ODI 11493630

Oct 12, 2022Engine

Check engine light code P052E

NHTSA ODI 11489056

Oct 9, 2022Transmission & drivetrainEngine

my engine failed at 82k odometer miles . replaced it with a new engine for $10065 . and they said it was fixed and working normal , 2nd engine failed at 111000 miles . and has warranty. they refuse to fix it for a 3rd time ...... this is a common problem with m274 engines. please help us m274 engine owners.... its a very widespread known problem...

NHTSA ODI 11488550

Sep 19, 2022Engine

Crank case to be replaced.

NHTSA ODI 11485163

Sep 12, 2022Engine

At approximately 65K miles, my PCV valve is bad and needs to be replaced at a cost of $1600. I saw lots of customer complaints for the same issue online, I think Mercedes should cover this item under recall.

NHTSA ODI 11484045

Jul 25, 2022Engine

Check engine light came in so I took it to a local auto shop. They ran the diagnostics and the code that appeared was P052E(Positive Crankcase Ventilation Regulation Valve Performance).

NHTSA ODI 11475641

Jul 18, 2022Engine

PCV valve causing check engine light to come on. 50,000 miles on vehicle.

NHTSA ODI 11474469

Jul 13, 2022Engine

Engine light was up at around 48700mile, diagnosis reading stated "PCV Regulator Valve Performance"

NHTSA ODI 11473638

Jul 12, 2022Transmission & drivetrainElectrical systemEngine

This is a plug-in hybrid car and twice in the last two weeks, the car while in motion on the road, has randomly turned off the engine and lost power. The gas pedal is unresponsive and all the alarms on screen flash and I have to coast to a stop. Most recently it was on a busy road and I barely missed being rear-ended. This is an unsafe situation and has happened twice and the only thing which I can do is come to complete stop, turn off the car and restart it and the problem goes away.

NHTSA ODI 11473539

Jul 11, 2022Engine

This is a known problem with The Mercedes cars from 2015 through 2018. The Service advisor said this is a know issue with this year, I asked can you do it for free because it is a Merc issue. He said he cannot do it. The cost for this repair is $2500 in Mercedes show room. These should be recalled and repair it for free for the customers.

NHTSA ODI 11473348

Jun 30, 2022Engine

Hello, I have 2016 Mercedes Benz c300(W205). Recently I got a Check Engine Light with P052E71. And the solution is to replace the Crankcase Ventilation Valve/Oil Separator, Intake Manifold. These parts are positioned on the right side bottom of the engine. It was a labor intensive work which required to remove multiple parts to gain access to the oil Separator. Considering the Issue Persists from W205 and Mercedes Benz has not done anything to rectify it, the cost is actually burdened upon the customer.

NHTSA ODI 11471877

Jun 23, 2022Engine

P052E emissions code

NHTSA ODI 11470665

Jun 10, 2022Transmission & drivetrainElectrical systemEngine

While driving the check engine light came on. The inside of the car started to smell like gas. A diagnostic check was performed at the Mercedes dealership and it was determined that there were 2 faults: low boost signal & ME control unit this was due to oil leaking from the crankcase vent line through the engine wiring harness and into the ME (engine module).

NHTSA ODI 11468718

Jun 6, 2022Electrical systemEngine

The contact owns a 2016 Mercedes-Benz C300. The contact stated that after turning off the vehicle and locking the doors; after a while, the vehicle would independently unlock the doors and then start up without driver input. The vehicle was taken to the dealer however, the mechanic was unable to determine the cause of the failure. The vehicle was not repaired. The manufacturer was not made aware of the failure. The approximate failure mileage was 43,000.

NHTSA ODI 11467780

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Working with the data? Download all 315 complaints as CSV · fetched from NHTSA July 25, 2026

How to use these: a complaint is one owner’s report, filed voluntarily and published unverified. Patterns matter more than any single story. If several owners describe the same failure at similar mileage, put that system at the top of your pre-purchase inspection list. Back to the full 2016 Mercedes-benz C-class Hybrid verdict →