If you’re anything like me, you know that under the hood is where the real magic happens. And when Mercedes-Benz rolls out new engines, especially with the kind of tech in the M254 and OM654 M, it’s like a love letter to anyone who adores smart engineering.
Whether you’re a fan of gasoline engines or still swear by diesel, these two powerplants tell a story of evolution, power, and a strong nod to the future. Let’s dig into what makes the Mercedes-Benz M254 and OM654 M engines so revolutionary—and how they’re changing the game for Mercedes-Benz cars and Mercedes-Benz vans alike.
M254: The New Generation Petrol Engine
Overview
The M254 is the successor to the M264 engine and part of Mercedes’ modular engine family, which allows for easier integration across different vehicle platforms. This new 2.0-liter four-cylinder engine powers models like the C-Class (W206) and comes equipped with cutting-edge technologies derived from the inline-six M256 engine.
Key Features
This new engine isn’t shy. It packs maximum power, smoother acceleration, and better fuel consumption. Think of it as the next-gen middle ground between efficiency and excitement. It delivers robust horsepower, balanced torque, and that unmistakable Mercedes finesse.
- Mild-Hybrid Technology: The M254 integrates a 48V electrical system and an Integrated Starter Generator (ISG) that provides up to 15 kW (20 hp) of additional power for short durations.
- Electric Auxiliary Compressor (eBooster): Improves throttle response and eliminates turbo lag by providing instant boost before the turbocharger kicks in.
- Segmented Cooling: Helps in thermal management, improving both cold start emissions and efficiency under load.
- Twinscroll Turbocharger: Enhances power delivery and fuel efficiency while minimizing turbo lag.
48-Volt Onboard Electrical System
One of the highlights is the 48-volt electrical system that supports many of the car’s functions and helps reduce the load on the main internal combustion engine. This isn’t just cool—it’s smart, and it’s part of what allows the M254 to offer greater fuel savings and lower fuel consumption overall.
Integrated Starter-Generator
At the heart of this system is the integrated starter generator. It’s not just for start-stop functions. It improves agile acceleration, allows smoother acceleration from a stop, and regenerates energy during braking. It also supports the engine during launch, making for seamless power delivery.
Enhanced Fuel Efficiency
With all this tech working together, the M254 engine stands out for its efficiency. Less fuel, more fun. Whether you’re in city traffic or flying down the highway, this engine ensures a balance of fuel economy and driving pleasure.
Performance Enhancements
- Power Output: Up to 272 hp (201 kW) in some versions, with additional boost from the mild hybrid system.
- Fuel Efficiency: Despite high power output, the M254 maintains excellent fuel economy and reduced emissions thanks to advanced combustion management.
And it doesn’t stop at efficiency. The M254 offers maximum torque right where you need it, making it ideal for both comfort and performance-oriented models. That’s the beauty of combining starter generator tech with turbocharging.
Applications
- C-Class (W206)
- E-Class facelift models
- Future compact Mercedes models
The M254 engine is Mercedes’ newest inline-four gasoline engine, and it’s not just a typical upgrade. It borrows the best of both worlds—the brains of a hybrid and the brawn of traditional combustion. It’s built for everything from sporty sedans to practical luxury vehicles.
Om654 M: The Updated Diesel Powerhouse
The OM654 M is an enhanced version of the existing OM654 2.0-liter diesel engine. The “M” stands for “Modular” or “Modified”, incorporating new technologies to meet stricter emissions regulations (Euro 6d) and to improve refinement and performance.
Overview Of The OM654 M Engine
Now let’s switch gears and talk about diesel. The OM654 M is a rework of the already impressive OM654 engine, itself a successor to the long-lived OM651 engine. It’s Mercedes’ answer to modern diesel engine demands—with more power, less emissions, and smarter construction.
Key Features
- Integrated Starter Generator (ISG): The OM654 M becomes the first diesel engine from Mercedes to be electrified with a 48V mild hybrid system, offering better efficiency and smoother engine starts.
- Increased Displacement: Compared to the original OM654, the OM654 M sees an increase in stroke (from 92.3 mm to 94.3 mm), bringing displacement to 1,993 cc.
- New Crankshaft and Pistons: For smoother operation and improved combustion dynamics.
- Advanced Emissions System: Includes an AdBlue injection system, diesel particulate filter (DPF), and NOx storage catalytic converters — all crucial for compliance with the latest emissions standards.
New Exhaust After-Treatment Systems
Mercedes didn’t hold back. The OM 654 M features improved catalyst coatings, redesigned exhaust gas recirculation, and other tweaks that dramatically cut exhaust gas pollutants. This matters—especially for regions with strict real driving emissions regulations.
Emission Reduction Technologies
Thanks to the updated stepped recess combustion process, steel pistons, and even reworked cylinder walls, this engine burns cleaner and runs cooler. That leads to low emissions, better combustion, and better performance across the board.
Diesel Engine Advancements
What sets the OM654 M apart is how refined it feels. Unlike old-school diesel engines, which were all noise and clatter, this one’s quiet, smooth, and surprisingly responsive. And it’s not just for Mercedes-Benz Sprinter vans—you’ll find it powering upscale Mercedes-Benz cars too.
Efficiency And Performance
You don’t have to sacrifice one for the other anymore. The OM654 M delivers strong horsepower and torque at low revs—think 380 Nm at around 3800 rpm—while sipping less fuel. That means lower emissions and satisfying pull.
- Power Output: Up to 265 hp, with a significant torque increase and assistance from the electric motor.
- Noise and Vibration Reduction: Substantial improvements have been made to NVH (Noise, Vibration, Harshness) characteristics, making it one of the smoothest diesels in its class.
Applications
- New C-Class (W206)
- E-Class facelift
- Other longitudinal engine layout vehicles
M254 Vs OM654 M: Quick Comparison
| Feature | M254 (Petrol) | OM654 M (Diesel) |
| Fuel Type | Petrol | Diesel |
| Displacement | 2.0 liters | 2.0 liters (1,993 cc) |
| Power | Up to 272 hp + 20 hp (ISG) | Up to 265 hp + ISG |
| Mild-Hybrid Support | Yes (48V ISG + eBooster) | Yes (48V ISG) |
| Turbocharging | Twinscroll + eBooster | Single turbo |
| Emissions Compliance | Euro 6d | Euro 6d |
| Applications | C-Class, E-Class, others | C-Class, E-Class, others |
The M254 and OM654 M represent the pinnacle of four-cylinder engine development from Mercedes-Benz. They blend performance, efficiency, and electrification to meet the demands of modern drivers and increasingly strict global emissions standards. Whether you’re a petrol enthusiast or a diesel fan, Mercedes has crafted two engines that bring luxury, power, and responsibility together in perfect harmony.
Technological Advancements In Both Engines
Whether you choose the gasoline M254 or the diesel OM654 M, you’re getting peak Mercedes-Benz engine innovation.
Lightweight Design Principles
Both engines were designed with lightweight construction in mind. Mercedes used a smart blend of aluminum and magnesium, which helps reduce the vehicle weight and boosts both performance and fuel economy.
Use Of Advanced Materials
From steel pistons to advanced cylinder coatings, the materials used increase durability and improve thermal efficiency. These choices are a big part of why these engines feel refined yet tough.
Contribution To Vehicle Weight Reduction
A lighter engine means better everything—quicker acceleration, tighter handling, and better fuel savings. You’ll notice it whether you’re driving a Sprinter van or a sleek C-Class sedan.
Impact On Driving Dynamics
Thanks to clever engineering, both engines contribute to dynamic driving. You’ll feel the difference in handling, rear wheel drive stability, and overall balance. These engines don’t just move the car—they shape how it feels.
Handling And Performance
Expect quick throttle response, especially from the M254 with its starter generator system. And the OM654 M? It gives traditional diesel fans that perfect combo of grunt and grace, especially when loaded up or hauling.
Consumer Satisfaction
Reviews from real-world drivers have been positive. Owners love the fuel savings, smooth operation, and quieter experience. Whether you’re in a Land Rover competitor or loyal to Mercedes, the leap in diesel engine refinement is obvious.
Driving Experience Improvements
Start-stop is smoother, acceleration is more linear, and the engines feel less stressed even under load. You’re getting the best of modern tech without losing the classic Mercedes diesel feel.
Meeting Global Emissions Standards
Both engines were developed to comply with the world’s strictest emissions rules—including Euro 6d and U.S. Tier 3. Mercedes made sure they could handle real driving emissions, not just lab tests.
Compliance With Regulations
With stronger exhaust gas treatment, better combustion control, and reduced fuel waste, these engines meet or exceed expectations globally. They prove that internal combustion engines still have a future when built smartly.
Sustainable Mobility Solutions
These engines are part of Mercedes’ larger move toward sustainable mobility. While EVs get the spotlight, these advanced engines are keeping the world moving without the carbon guilt.
Mercedes’ Commitment To Environmental Standards
From developing low emissions technology to smarter fuel economy systems, Mercedes is serious about reducing its footprint. It’s not just about passing tests—it’s about making lasting change.
Mercedes’ Innovative Approach To Engine Design
The M254 and OM654 M represent decades of evolution. They’re proof of Mercedes’ commitment to engineering excellence—refining what works, rethinking what doesn’t, and always looking forward.
Commitment To Engineering Excellence
Every bolt, piston, and cylinder reflects that attention to detail. Whether you’re in a luxury sedan or a Mercedes-Benz Sprinter, you feel the craftsmanship.
Future Of Mercedes Engines
As we move toward hybrid and electric futures, engines like the M254 and OM654 M show that Mercedes-Benz engines still have room to grow. Cleaner, stronger, smarter—that’s the way forward.
Innovations In Automotive Technology
In the end, these engines are more than just parts—they’re a vision of where cars, vans, and mobility as a whole are headed. Intelligent, efficient, and above all, made for drivers who expect more.
Conclusion
The M254 and OM654 M engines show that Mercedes-Benz still leads in smart combustion tech. Whether you prefer gasoline or diesel, these engines offer strong torque, smooth acceleration, and impressive fuel economy—all while meeting global emissions standards.
From city drives to heavy-duty hauls in a Sprinter van, they deliver real-world efficiency without losing that Mercedes feel. Thoughtfully engineered with future mobility in mind, they prove that innovation isn’t just electric—it’s also under the hood. For those who still love the roar of a refined engine, this is power with a purpose.
Frequently Asked Questions
1.What Is The Mercedes M254 Engine?
The M254 engine is Mercedes-Benz’s latest 4-cylinder gasoline engine, designed for better fuel economy, torque, and smoother acceleration. It features a 48-volt electrical system and an integrated starter generator to enhance power and efficiency.
2.What Does OM654 M Mean In Mercedes Diesel Engines?
The OM654 M is an upgraded version of the OM654 engine, optimized for better emissions, fuel savings, and real driving emissions compliance. It includes advanced features like exhaust gas recirculation and improved catalyst coatings.
3.How Efficient Are These Engines In Real-World Driving?
Both engines meet stringent real driving emissions standards and are built to minimize fuel consumption. Whether it’s in Mercedes-Benz vans like the Sprinter or Mercedes-Benz cars, they provide real-world performance and lower emissions.
4.What Vehicles Use The M254 And OM654 M Engines?
You’ll find the M254 in newer Mercedes-Benz cars, especially sedans and coupes. The OM654 M is popular in diesel models, including the Mercedes-Benz Sprinter van and select luxury vehicles across the brand’s global lineup.
5.How Do These Engines Improve The Driving Experience?
Expect agile acceleration, rear-wheel drive balance, and a refined ride. The combination of steel pistons, optimized cylinder walls, and lightweight design boosts handling while reducing engine stress.
6.Are These Engines Eco-Friendly?
Yes. Mercedes incorporated sustainable mobility solutions into both engines. With tech like the stepped recess combustion process, they achieve low emissions without sacrificing power or durability.
7.What Makes These Mercedes Engines Different From Older Ones Like The OM651?
Compared to the OM651 engine, the OM654 M offers better combustion, maximum torque at lower RPMs (around 3800 rpm), quieter operation, and enhanced fuel economy. It’s a true leap forward for diesel engines.
8.How Do These Engines Support Mercedes’ Environmental Goals?
Both engines reflect the brand’s commitment to engineering excellence and environmental standards. They are part of Mercedes’ broader push toward greener combustion and smarter energy usage across their vehicle lineup.