Table of Contents
Mercedes OM654 Inline‑4 Diesel Engine (2016–Present)
The OM654 is Mercedes‑Benz’s fourth‑gen 2.0 L inline‑4 Euro 6 diesel engine aluminum block and head, Nanoslide-coated bores, single-stage variable‑geometry turbo, and integrated DPF/DPF & SCR systems. It delivers up to 265 hp and 550 Nm, while being ~17% lighter and more efficient than its predecessor
In this article, we’ll break down everything you need to know about the OM654 from its innovative technology to common reliability concerns, maintenance tips, and model applications.
OM654 Reliability
The Mercedes-Benz OM654 engine represents the brand’s latest generation of four-cylinder diesel powerplants, designed to meet stricter emission standards while offering improved fuel economy, performance, and durability. First introduced in 2016, this all-aluminum engine is now found across many modern Mercedes models. But despite its cutting-edge design, the OM 654 isn’t without its problems.
OM654 Engine Views
OM654 Engine Overview The OM654 is a 2.0L four-cylinder turbocharged diesel engine developed to replace the OM651. It features:
- – All-aluminum block and head (for weight reduction)
- – Single turbocharger (variable geometry)
- – Integrated exhaust manifold
- – Close-coupled diesel particulate filter (DPF)
- – Advanced piezo injectors for improved fuel atomization
This engine is Euro 6 compliant and designed for enhanced thermal efficiency and lower NOx emissions.
OM654 Engine Variants & Model Applications
| Variant | Displ. (cc) | Power & Torque | Used In (year–model) |
|---|---|---|---|
| OM654 DE16 G SCR | 1,597 | 90–118 kW / 300–360 Nm | C180d/C200d, compact range |
| OM654 DE20 G SCR | 1,950 | 110–143 kW / 360–400 Nm | C220d, C 300d, E220d, GLC 200‑220d, W167, C257 |
| OM654 M DE20 G SCR (M‑HEV) | 1,992 | Up to 200 kW/550 Nm | C/E 300d hybrids with 48V starter-generator |
Key Technical Specs
- – Bore × Stroke: 82 × 92.3 mm
- – Compression Ratio: 15.5 : 1
- – Dry Weight: ~168 kg (vs 202 kg OM651)
- – Turbo: Single turbo, VGT, water-cooled
- – Fuel: 4th-gen common rail, 2050 bar
- – Emissions: Euro 6; integrated SCR & DPF
The aluminum block design makes the engine lighter, contributing to better fuel efficiency and handling. The use of a single-stage turbocharger ensures a balance between performance and fuel economy.
Performance and Efficiency
The OM 654 engine is celebrated for its remarkable performance and efficiency. It delivers robust power, ensuring a dynamic driving experience. One of the standout features of this engine is its fuel efficiency, achieved through advanced combustion processes and reduced internal friction.
Fuel Efficiency & Performance This engine delivers strong low-end torque, excellent highway efficiency, and smooth refinement. It’s particularly praised for:
- – Reduced engine noise compared to the OM651
- – Improved throttle response
- – Better fuel economy (up to 20% improvement)
These traits make it ideal for both city and long-distance driving.
Technologies and Innovations
The OM 654 engine incorporates several cutting-edge technologies, including:
CAMTRONIC Valve Lift Adjustment: This system optimizes the valve lift for improved fuel efficiency and reduced emissions.
Low-Friction Cylinder Coatings: These coatings reduce internal friction, enhancing engine efficiency and longevity.
Advanced Turbocharging: The single-stage turbocharger ensures optimal performance across different driving conditions.
These innovations not only improve performance but also ensure compliance with stringent emission standards.
OM654 problems & Fixes
| Issue | Symptoms & Diagnosis | Recommended Fix & Maintenance |
|---|---|---|
| Injector seal leaks | Injector-specific oil seepage (~£600 repair) | Replace seals, inspect injectors regularly |
| Timing chain wear | Rattle, occasional recall on early units | Monitor noise; time chain replacement during major services |
| Camshaft bearing wear | Turbo lag, noise; Sprinter forums highlight | Inspect cam followers/rockers; replace bearings proactively |
| EGR/DPF/AdBlue issues | Emissions warnings, limp mode | Clean or replace EGR & DPF; maintain quality AdBlue fluid |
| Turbo/Oil leaks | Boost drop, oil under turbo housing | Inspect hoses, gaskets; replace if cracked use MB-approved oil |
Learn about an issue in Mercedes-Benz GLE W167 Equipped with OM 654 in the next link.
Car Dies While Driving: Case Study & Solution
Engine is Burning Oil: Solve it Easily
AdBlue System Malfunction: Full Repair Guide
Recommended Maintenance Schedule
- – Oil & filter: MB 229‑51 synthetic, every 10k mi
- – Injector seals: Inspect at major service
- – Cam/logging wear: Listen for noise at ~100k mi, check bearings
- – Timing chain: Monitor for rattle, usually around 150k km
- – ADBlue & emissions: Monthly top-up/check; perform forced DPF regen
- – Turbo & hoses: Inspect at each service for leaks or cracks
Comparisons with Other Engines
OM654 vs OM651: What’s the Difference?
| Feature | OM651 | OM654 |
|---|---|---|
| Material | Cast iron block | Aluminum block |
| Emissions Standard | Euro 5 / early Euro 6 | Euro 6d |
| Fuel Efficiency | Good | Better (~15-20% improvement) |
| Turbo System | Twin-turbo in some models | Single VGT |
| Refinement | Noisier | Quieter and smoother |
When compared to its predecessor, the OM651, the OM 654 offers improved performance and efficiency. The newer engine features a lighter aluminum block and advanced turbocharging, which contribute to better overall performance.
Compared to the OM656, the OM 654 is more compact and fuel-efficient, making it suitable for a wider range of Mercedes models.
Which Mercedes models use the OM654 engine?
Applications in Mercedes Models
The OM654 engine is used in various Mercedes-Benz models, including:
Mercedes E-Class: Known for its luxury and performance, the E-Class W213 benefits greatly from the power and efficiency of the OM 654 engine.
Mercedes C-Class: The compact design of the C-Class W205 Facelift pairs well with the OM654, offering a balanced driving experience.
Mercedes GLC: This SUV model enjoys enhanced performance and fuel efficiency, thanks to the advanced diesel engine.
Mercedes GLE W167: This SUV model enjoys enhanced performance and fuel efficiency, thanks to the advanced diesel engine.
Owners of these models often praise the engine for its smooth performance and reliability.
Future Developments and Updates
Mercedes continues to innovate, and the OM 654 engine is expected to receive updates that further enhance its performance and efficiency.
Future developments might include improved turbocharging technology and even lower emission outputs, keeping Mercedes at the forefront of diesel engine technology.
Exhaust Treatment
Conclusion
The Mercedes OM 654 engine is a marvel of modern engineering, combining performance, efficiency, and advanced technology. It powers a range of Mercedes models, offering a dynamic driving experience and impressive fuel economy. Regular maintenance and an understanding of common issues can help owners get the most out of their engine.
Frequently Asked Questions
Is the OM654 engine reliable?
Yes, when maintained properly. Regular oil, injector seal checks, and emissions care ensure durability.
How often should I inspect the timing chain?
Listen for rattle around 100k–150k km. Have it inspected and tensioners checked during major service.
Should I worry about injector seal leaks?
Yes, seal failures have been reported. Have them checked at major service intervals and replaced as needed.
How do I prevent EGR/DPF issues?
Maintain AdBlue levels, do regular long drives to trigger active DPF regen, and clean EGR valves when needed.
