The Mercedes-Benz C 250 CDI BlueEFFICIENCY, produced between 2009 and 2011, was a significant variant within the W204 C-Class range. Positioned as a fuel-efficient and refined option, it offered a compelling blend of performance and economy, primarily targeting the European market where diesel engines were highly favored. This model aimed to provide an accessible entry point into the C-Class lineup while maintaining the brand’s reputation for luxury and build quality. It bridged the gap between the lower-powered C 200 CDI and the more performance-focused C 300 CDI, appealing to buyers who prioritized efficiency and comfortable cruising.
Technical Specifications
| Brand | Mercedes-Benz |
| Model | C-class |
| Generation | C-class (W204) |
| Type (Engine) | C 250 CDI BlueEFFICIENCY (204 Hp) 5G-TRONIC |
| Start of production | 2009 |
| End of production | 2011 |
| Powertrain Architecture | Internal Combustion engine |
| Body type | Sedan |
| Seats | 5 |
| Doors | 4 |
| Fuel consumption (urban) | 8.1-8.5 l/100 km (29 – 27.7 US mpg) |
| Fuel consumption (extra urban) | 4.4-5.1 l/100 km (53.5 – 46.1 US mpg) |
| Fuel consumption (combined) | 5.8-6.4 l/100 km (40.6 – 36.8 US mpg) |
| CO2 emissions | 153-167 g/km |
| Fuel Type | Diesel |
| Acceleration 0 – 100 km/h | 7 sec |
| Acceleration 0 – 62 mph | 7 sec |
| Acceleration 0 – 60 mph | 6.7 sec |
| Maximum speed | 240 km/h (149.13 mph) |
| Emission standard | Euro 5 |
| Weight-to-power ratio | 7.5 kg/Hp |
| Weight-to-torque ratio | 3.1 kg/Nm |
| Power | 204 Hp @ 4200 rpm |
| Torque | 500 Nm @ 1600-1800 rpm (368.78 lb.-ft. @ 1600-1800 rpm) |
| Engine layout | Front, Longitudinal |
| Engine Model/Code | OM 651.911 |
| Engine displacement | 2143 cm3 (130.77 cu. in.) |
| Number of cylinders | 4 |
| Engine configuration | Inline |
| Cylinder Bore | 83 mm (3.27 in.) |
| Piston Stroke | 99 mm (3.9 in.) |
| Compression ratio | 16.2:1 |
| Number of valves per cylinder | 4 |
| Fuel injection system | Diesel Commonrail |
| Engine aspiration | Twin-Turbo, Intercooler |
| Valvetrain | DOHC |
| Engine oil capacity | 6.5 l (6.87 US qt | 5.72 UK qt) |
| Kerb Weight | 1540 kg (3395.12 lbs.) |
| Max. weight | 2120 kg (4673.8 lbs.) |
| Max load | 580 kg (1278.68 lbs.) |
| Trunk (boot) space | 475 l (16.77 cu. ft.) |
| Fuel tank capacity | 59 l (15.59 US gal | 12.98 UK gal) |
| Length | 4581 mm (180.35 in.) |
| Width | 1770 mm (69.69 in.) |
| Height | 1447 mm (56.97 in.) |
| Wheelbase | 2760 mm (108.66 in.) |
| Drivetrain Architecture | Rear wheel drive |
| Number of gears | 5 |
| Gearbox type | automatic transmission G-TRONIC |
Powertrain & Engine Architecture
The core of the C 250 CDI BlueEFFICIENCY is the OM 651.911, a 2.1-liter inline-four cylinder diesel engine. This engine represented a significant advancement in diesel technology for its time, incorporating common-rail direct injection and a sophisticated twin-turbocharger system. The twin-turbo configuration, utilizing a smaller, low-inertia turbo for rapid response and a larger turbo for peak power delivery, contributed to the engine’s remarkably flat torque curve. A high compression ratio of 16.2:1, typical for diesel engines, maximized thermal efficiency. The 5G-TRONIC automatic transmission, a five-speed torque converter automatic, was specifically tuned to complement the engine’s characteristics, prioritizing smooth gear changes and fuel economy. While not the most cutting-edge transmission available at the time, it was known for its dependability and comfortable operation.
Driving Characteristics
The C 250 CDI BlueEFFICIENCY provided a distinct driving experience compared to its gasoline-powered counterparts or the more powerful C 300 CDI. The engine produced 204 horsepower, but the real strength lay in its 368 lb-ft of torque, readily available from just 1600 rpm. This provided ample power for everyday driving and overtaking. While not a performance-oriented vehicle, the C 250 CDI could accelerate from 0 to 60 mph in approximately 6.7 seconds. The 5G-TRONIC transmission, while smooth, wasn’t particularly quick to downshift, occasionally resulting in a slight delay when demanding immediate acceleration. Compared to the manual transmission options, the automatic prioritized convenience over driver engagement. The overall focus was on relaxed, efficient cruising rather than sporty performance.
Equipment & Trim Levels
The C 250 CDI BlueEFFICIENCY generally came well-equipped as standard. Features included automatic climate control, a multi-function steering wheel, power windows and mirrors, and a basic audio system. Interior upholstery was typically cloth, with leather options available. Optional extras included a premium sound system, a navigation system, a sunroof, and parking sensors. The “BlueEFFICIENCY” designation signified the inclusion of fuel-saving technologies like start-stop functionality and optimized aerodynamic features. Trim levels varied slightly by market, but the C 250 CDI generally occupied the mid-range position within the C-Class lineup, offering a balanced combination of features and price.
Chassis & Braking
The W204 C-Class utilized a fully independent suspension system, featuring McPherson struts at the front and a multi-link setup at the rear. This configuration delivered a comfortable ride while maintaining respectable handling. The C 250 CDI, due to its increased weight, often had slightly stiffer spring rates compared to the lighter C 200 models. Braking systems typically consisted of ventilated discs at the front and solid discs at the rear, with ABS (Anti-lock Braking System) as standard equipment. The steering was a hydraulic power-assisted rack and pinion system, providing precise and responsive control.
Market Reception & Comparison
The C 250 CDI BlueEFFICIENCY received generally positive reviews from automotive critics. It was lauded for its fuel efficiency, comfortable ride quality, and refined engine. Some reviewers did note that the 5G-TRONIC transmission felt somewhat dated compared to newer automatic gearboxes. Compared to the C 200 CDI, the C 250 CDI offered a noticeable performance improvement without a significant increase in fuel consumption. In contrast to the C 300 CDI, it provided a more economical option, albeit with less power. Its primary appeal lay in its ability to deliver a premium driving experience with reduced running costs.
Legacy
The OM 651 engine family, including the 2.1-liter variant powering the C 250 CDI, has proven to be exceptionally durable and reliable. These engines are known for their longevity and relatively low maintenance requirements, provided they receive regular servicing. In the used car market, the C 250 CDI BlueEFFICIENCY remains a popular choice, particularly for buyers seeking a comfortable, fuel-efficient, and well-built sedan. While diesel technology has continued to evolve, the W204 C 250 CDI continues to represent a strong value proposition and a testament to Mercedes-Benz’s engineering expertise.
