10.0

really awful
Crashes / Fires:
0 / 2
Injuries / Deaths:
0 / 0
Average Mileage:
5,234 miles

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« Read the previous 20 complaints

problem #36

Dec 202022

C300

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

- East Islip, NY, USA

problem #35

Sep 012022

C300

  • miles
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.

- San Diego, CA, USA

problem #34

Aug 252022

C300

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

- Moyock , NC, USA

problem #33

Nov 102022

C300

  • miles
(P052e) positive crankcase ventilation regularly valve

- Richmond , TX, USA

problem #32

Oct 122022

C300

  • miles
Check engine light code P052E

- Manassas , VA, USA

problem #31

Oct 082022

C300

  • miles
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...

- Sioux Falls, SD, USA

problem #30

Sep 012022

C300

  • miles
Crank case to be replaced.

- Overland Park, KS, USA

problem #29

Sep 122022

C300

  • miles
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.

- Lees Summit, MO, USA

problem #28

Jul 252022

C300

  • miles
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).

- Bellevue, NE, USA

problem #27

Jul 012022

C300

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

- Westerville, OH, USA

problem #26

Jul 102022

C300

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

- Renton, WA, USA

problem #25

May 122022

C300

  • miles
P052E emissions code

- Stony Point , NY, USA

problem #24

Jun 082022

C300

  • miles
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).

- Maumelle, AR, USA

problem #23

Jun 012022

C300

  • 43,000 miles
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.

- San Diego, CA, USA

problem #22

May 022022

C300

  • miles
Failure in the performance of the Crankcase Ventilation Regulator valve, research online indicates this is a very common issue especially in w205s. Mercedes has omitted this from their gasoline powered, emissions control warranty, but is listed under the BLUtech/ Diesel warranty. The car will fail the emissions test, and Mercedes Models have a recurring problem with this part which is charged out of pocket once vehicle warranty is up.

- North Andover, MA, USA

problem #21

Apr 302022

C300

  • miles
Check engine light and error code P052E - Positive Crankcase Ventilation regulator Valve Performance. Within a year of having the same error code repaired using warranty, I'm again getting the same error code. This is a very expensive repair costing upwards of $2000 as per dealer and I'm having to do this repair again. This should be some kind of manufacturing defect and needs to be recalled.

- Bolingbrook, IL, USA

problem #20

Apr 062022

C300

  • miles
- CRANK CASE VENT VALVE malfunctioned, it was available for inspection upon request with fee - It made oil burning smell - The problem has been confirmed by a dealer and replaced with an expensive fee - Engine check light was

- Dix Hills, NY, USA

problem #19

Apr 042022

C300

  • miles
The vehicle lost power on the Freeway, coasted the off-ramp, and came to a stop, the dealership after describing the issue said that it sounded like a bad piston. Said they have had a couple come in with the same problem. Their diagnosis was a bad piston a day later. The mileage is less than 50,000 miles and the car was driven daily to work 4 miles each way. There were no warnings or symptoms of failure prior to happening. The warranty on the vehicle has expired on 7/1/2021

- Norwalk, CA, USA

problem #18

Feb 162022

C300

  • miles
Around the 58,000 mile mark my check engine light on my 2016 Mercedes C300 4MATIC came on. I checked the gas cap, as that can set off the check engine light, and the check engine light went off the next day. 3 days later the check engine light comes on again, so I repeated the steps of taking the gas cap off and putting back on. The light did not go off the next day. 5 days later the light goes off again. This happened several times over a span of 2-3 weeks. I then take my car to be checked with an OBD-II Scanner. It read off every time the check engine light had been on, which was several times. The error code the scanner displayed was "P052E" and a description of "Positive Crankcase Ventilation Regulator Valve Performance". It was the same code multiple times. At this point I did a little research to see if this was something I could repair. While researching the issue, I found that case after case of the very same issue was being reported by owners of cars like mine. I then came across a post that said they had reported the issue to NHTSA and was told that it was such a widespread issue that if "A few more cars are reported to have this issue then a recall would potentially be issued because of the amount of cars that are having the exact same issue at very similar mileages, and it is a very expensive repair. I just feel that this is too common of a problem by the same cars, at the same mileages from the same Manufacturer.

- Sevierville, TN, USA

problem #17

Feb 012022

C300

  • miles
P052e positive crankcase ventilation

- Binghamton , NY, USA

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