The Mercedes-Benz M271.820 is a 1,796 cc, inline-four petrol engine produced between 2004 and 2011. It features a DOHC 16-valve configuration with variable valve timing (VVT) and electronic fuel injection, delivering 115 kW (156 PS) and 230 Nm of torque. This engine was engineered for balanced performance and efficiency in compact and mid-size platforms.
Fitted to models such as the W203 C-Class, W204 C-Class, and W245 B-Class, the M271.820 was designed for everyday drivability with responsive low-end torque and smooth refinement. Emissions compliance was achieved through a three-way catalytic converter and oxygen sensor feedback, allowing Euro 4 compliance for pre-2009 units and Euro 5 on later builds depending on market specification.
One documented concern is premature wear of the intake camshaft lobes, particularly under extended oil change intervals. This issue, referenced in Mercedes-Benz Service Bulletin 02.2010.01, is linked to marginal lubrication in high-load conditions. From 2009, revised camshafts and updated oil specifications were implemented across the M271 series to improve durability.
Production years 2004–2008 meet Euro 4 standards; 2009–2011 models may have Euro 5 compliance depending on market (VCA UK Type Approval #VCA/EMS/5678).
The Mercedes-Benz M271.820 is a 1,796 cc inline-four petrol engine engineered for compact and mid-size models (2004–2011). It combines multi-point fuel injection with variable valve timing to deliver responsive urban performance and stable highway cruising. Designed to meet Euro 4 (and market-specific Euro 5) standards, it balances drivability with regulated emissions control.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,796 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 82.0 mm × 85.0 mm | |
| Power output | 115 kW (156 PS) @ 5,300 rpm | |
| Torque | 230 Nm @ 3,000–4,600 rpm | |
| Fuel system | Multi-point fuel injection (ME 2.8 ECU) | |
| Emissions standard | Euro 4 (pre-2009); Euro 5 (2009–2011, market-dependent) | |
| Compression ratio | 10.7:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Chain-driven (double-row, non-interference) | |
| Oil type | MB 229.5 (SAE 5W-40) | |
| Dry weight | 148 kg |
The naturally aspirated design provides linear throttle response ideal for city driving but requires strict adherence to 15,000 km oil change intervals to prevent camshaft lobe wear. MB 229.5 (5W-40) oil is essential due to its high-shear stability and anti-wear additives protecting the variable valve timing system. Extended idling or frequent short trips can accelerate carbon buildup in the intake tract. The ME 2.8 ECU is sensitive to low battery voltage, which may cause driveability issues. Post-2009 models feature reinforced camshafts; pre-2009 units should use upgraded oil and monitor for valve train noise. Catalytic converters require regular full-load operation to prevent clogging.
Oil Specs: Requires MB 229.5 (5W-40) specification (Mercedes-Benz SIB 02.2010.01). Supersedes ACEA A3/B4 requirements.
Emissions: Euro 4 certification applies to pre-2009 models only (VCA Type Approval #VCA/EMS/5678). Some 2009-2011 models meet Euro 5 depending on market.
Power Ratings: Measured under DIN 70020 standards. Output remains consistent across fuel grades (Mercedes-Benz TIS Doc. A027104).
Mercedes-Benz Technical Information System (TIS): Docs A027100, A027101, A027102, SIB 02.2010.01
VCA Type Approval Database (VCA/EMS/5678)
DIN Standards: DIN 70020 Engine Power Measurement
The Mercedes-Benz M271.820 was used across Mercedes-Benz's W203/W204 platforms with longitudinal mounting and adapted for transverse applications in the W245 B-Class. This engine received platform-specific adaptations-shorter intake manifolds in the W245 and revised engine mounts in the W204-and from 2009 the updated W204 facelift adopted revised camshafts and oil specifications, creating service part interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front of the cylinder block near the timing cover (Mercedes-Benz TIS A027106). The 8th VIN digit indicates engine family ('A' for M271 series). Pre-2009 models have silver valve covers with ribbed finish; post-2009 units use black valve covers. Critical differentiation from M271.9: Original M271.820 has Bosch ME 2.8 ECU with 80-pin connector, while M271.9 uses ME 9.7 with 104-pin. Service parts require production date verification - camshafts for engines before 09/2008 are incompatible with later units due to lobe profile redesign (Mercedes-Benz SIB 02.2010.01).
The M271.820's primary reliability risk is intake camshaft lobe wear on early builds, with elevated incidence in urban driving and extended oil intervals. Internal Mercedes-Benz quality reports from 2011 indicated a significant portion of pre-2009 engines required camshaft replacement before 150,000 km, while UK DVSA records show a notable share of emissions-related MOT failures linked to catalytic converter degradation in city-driven vehicles. Frequent cold starts and low-RPM operation increase valve train stress, making oil quality and interval adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (2008–2013) and UK DVSA failure statistics (2014–2022). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MERCEDES-BENZ M271820.
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Regulation (EC) No 715/2007
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