Mercedes-Benz C300 Engine Problems
Owners have filed 455 complaints with NHTSA about engine problems on the Mercedes-Benz C300 across 17 model years. The 2015 model year has the most (127). The words owners use most often: “crankcase ventilation” (21% of reports).
- 455engine complaints
- —median miles at failure
- 2mention a crash
- 2mention an injury
- 3related recalls
- $2,350typical repair cost reported by owners
- 39%of reports with a speed happened at 50+ mph
What owners describe
Phrases that appear unusually often in these complaints compared with complaints about other cars.
- Crankcase ventilation: mentioned in 94 of 455 complaints (21%)
- Code P052E: mentioned in 56 of 455 complaints (12%)
- Regulator valve: mentioned in 28 of 455 complaints (6%)
How much does it cost to fix?
Owners who wrote down what they paid or were quoted put the typical engine repair on the Mercedes-Benz C300 at $2,350, and half of them between $2,000 and $3,300.
Based on 32 NHTSA complaints about this problem alone that state a repair bill or quote (2017–2026), converted to 2026 dollars with the U.S. consumer price index. These are owners' own figures, not a quote: they include dealer quotes, and owners who file complaints often faced larger repairs, so they can run higher than typical shop prices. Prices vary by shop, region and warranty coverage. How we calculate this.
At what mileage do engine problems happen?
Based on 134 complaints that reported the odometer reading.
How serious are the reports?
Of 455 complaints, 2 mention a crash, 8 a fire, 2 an injury.
Mercedes-Benz C300 engine complaints by model year
| Model year | Engine complaints | Share of that year | Median miles |
|---|---|---|---|
| 2024 C300 | 2 | 18% | — |
| 2023 C300 | 2 | 9% | 3,900 |
| 2022 C300 | 2 | 8% | — |
| 2021 C300 | 8 | 57% | 87,039 |
| 2020 C300 | 8 | 24% | 77,500 |
| 2019 C300 | 17 | 25% | 5,350 |
| 2018 C300 | 34 | 34% | 14,000 |
| 2017 C300 | 77 | 36% | 36,000 |
| 2016 C300 | 93 | 32% | 23,750 |
| 2015 C300 | 127 | 33% | 53,000 |
| 2014 C300 | 2 | 2% | — |
| 2013 C300 | 8 | 3% | 75,000 |
| 2012 C300 | 5 | 2% | 53,000 |
| 2011 C300 | 10 | 2% | 78,000 |
| 2010 C300 | 13 | 3% | 70,000 |
| 2009 C300 | 16 | 3% | 70,000 |
| 2008 C300 | 31 | 5% | 80,000 |
When owners reported it
Related recalls (3)
Exterior lighting:lighting control module:software; engine and engine cooling:engine:engine control module (ecu/ecm):software; electronic stability control (esc):control module:software
Model years: 2008, 2009
Problem: Mercedes-Benz USA, LLC (MBUSA) is recalling certain 2010 E350, 2014 G550, 2008-2009 C300, 2008 C350, 2009 CLK550, 2007 SL550, SLK280, and 2008 SLK350 vehicles. Various control units may have been updated with incorrect software configuration during a service repair. This can result in various system failures, such as loss of drive power, reduced exterior lighting, or loss of dynamic control functions, including stability and traction control.
Risk: Various system failures, such as loss of drive power, reduced exterior lighting, or loss of dynamic control functions including stability and traction control, can increase the risk of a crash.
Fix: Dealers will update the software configuration on the affected control units, free of charge. Owner notification letters were mailed May 3, 2022. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2022040003.
Engine and engine cooling:engine:gasoline:turbo/supercharger
Model years: 2020
Problem: Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2020 C300, E350, and GLC300 vehicles equipped with turbocharged 4-cylinder gasoline engines. The screws that retain the turbocharger oil feed and return lines may not have been properly tightened, possibly resulting in an oil leak.
Risk: An oil leak in the presence of an ignition source such as hot engine or exhaust components can increase the risk of a fire.
Fix: MBUSA will notify owners, and dealers will inspect the turbocharger oil lines and tighten them as necessary, free of charge. The recall began August 17, 2020. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2020070017.
Electrical system:starter assembly; engine and engine cooling:engine
Model years: 2015, 2016, 2017
Problem: Mercedes-Benz USA, LLC. (MBUSA) is recalling certain 2015-2017 C300 4Matic, C300, CLA250, CLA250 4Matic and CLA45 AMG vehicles, 2017 C300 4Matic Cabrio, C300 4Matic Coupe, C300 Cabrio, C300 Coupe, E300, E300 4Matic, E400 4Matic Wagon, E43 AMG 4Matic, GLA250, GLA250 4Matic and GLC300 4Matic Coupe vehicles and 2016 C350e and GLC300 vehicles and 2016-2017 C450 4Matic AMG Sport and GLC300 4Matic vehicles. In the event that the engine or transmission cannot turn over, the starting current limiter may overheat from the repeated attempts of the starter motor attempting to start the vehicle.
Risk: If the starting current limiter overheats, the surrounding components can melt, increasing the risk of a fire.
Fix: MBUSA will notify owners, and dealers will install an additional fuse in the electrical line to the starter, free of charge. The recall began August 31, 2017. Owners may contact MBUSA customer service at 1-800-367-6372. MBUSA's number for this recall is 2017080002.
What owners report
Short excerpts of recent complaints, with personal details removed. Full reports are on NHTSA.gov.
The M264 2.0L engine suffered a catastrophic internal failure. While making a left turn at an intersection, the vehicle suddenly shut off and stalled, leaving the car stranded in active traffic and creating an immediate safety risk. Prior to the shutdown, the check engine light came on accompanied…
The vehicle experienced a severe safety issue involving a sudden loss of motive power in active traffic. 1. Initial Symptoms & Diagnosis: Recently, the Check Engine Light illuminated. Although the light turned off before my scheduled appointment, I still brought the vehicle to an authorized…
The contact owns a 2021 Mercedes-Benz C 300. The contact stated that while depressing the accelerator pedal, there was a loud knocking sound coming from the engine compartment while accelerating. There were no warning lights illuminated. The vehicle was taken to the dealer to be diagnosed, and it…
2017 Mercedes c300 the switchover valve in the diagnostic module of the evaporative emission control system is jammed open. This issue was called for recall for models 2018 or later, but 2017 was not part of it.
Driving a 2024 mercedes c300 on the florida turnpike in the left lane at 70 mph the engine suddenly slowed down. While the vehicle slowed in heavy traffic i was able to merge to the outside lane where it stopped. I called mercedes emergency who suggested waiting a while and try starting the vehicle…
Frequently asked questions
Do all Mercedes-Benz C300s have engine problems?
No. NHTSA has 455 owner complaints about engine for the Mercedes-Benz C300. Complaint data shows that the problem is reported, not how many of all cars sold are affected.
Was there a recall on the Mercedes-Benz C300 engine?
Yes: 3 safety recalls list engine. Check your VIN on NHTSA.gov to see whether the fix was done on your car.
How much does it cost to fix engine problems on the Mercedes-Benz C300?
Owners report a typical cost of $2,350 (half paid between $2,000 and $3,300), from 32 complaints that state a repair bill or quote, in 2026 dollars.
What do owners say about engine problems on the Mercedes-Benz C300?
The most frequent phrase is “crankcase ventilation”, in 94 of 455 complaints, followed by “code p052e” (56).
Other Mercedes-Benz C300 problems
- Air Bags problems (1,213)
- Electrical System problems (750)
- Steering problems (493)
- Structure problems (380)
- Exterior Lighting problems (310)
- Suspension problems (307)
- Fuel/propulsion System problems (261)
- Power Train problems (119)
See all Mercedes-Benz C300 problems.