The Mercedes — Benz M 112.945 is a 2,799 cc, V6 naturally aspirated petrol engine produced between 1997 and 2002. It belongs to the M112 engine family, featuring a single overhead camshaft (SOHC), 24 — valve configuration, and electronic multi — point fuel injection (ME — SFI). In standard tune it delivered 140 kW (190 PS), providing smooth and refined performance for mid — size and executive applications.
Fitted to models including the W210 E — Class, W202 C — Class, and CLK Co…
Production years 1997–2002 meet Euro 3 emissions standards (EC Directive 98/69/EC, VCA UK Type Approval #VCA/EMS/6793).
The Mercedes-Benz M 112.945 is a 2,799 cc V6 petrol engine engineered for mid-size and executive platforms (1997–2002). It combines SOHC valvetrain architecture with Bosch ME-SFI electronic fuel injection to deliver linear power delivery and driving refinement. Designed to meet Euro 3 emissions requirements, it balances performance with OBD-II-compliant diagnostics and catalyst efficiency.
| Parameter | Value | Source |
|---|---|---|
Displacement | 2,799 cc | |
Fuel type | Petrol | |
Configuration | V6, SOHC, 24-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 88.0 mm × 76.6 mm | |
Power output | 140 kW (190 PS) @ 5,500 rpm | |
Torque | 270 Nm @ 3,000 rpm | |
Fuel system | Bosch ME-SFI electronic multi-point injection | |
Emissions standard | Euro 3 (EC Directive 98/69/EC) | |
Compression ratio | 10.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Chain-driven (dual-row, tensioner-equipped) | |
Oil type | SAE 5W-40 (API SL/CF) | |
Dry weight | 175 kg |
The Mercedes-Benz M 112.945 was used across Mercedes-Benz's W210, W202, and C208 platforms with longitudinal mounting and no licensed external applications. This engine received platform-specific adaptations-fuel mixture tuning for automatic transmission pairings in the W210 and revised intake manifolds in the W202-and from 2002, the W211 E-Class transitioned to the M112.957 variant with revised cam profiles, ending M112.945 production. All adaptations are documented in OEM technical bulletins.
The M 112.945's primary reliability risk is timing chain tensioner failure, with elevated incidence in high-mileage or short-trip usage. Internal Mercedes-Benz quality reports from 2001 indicated a measurable share of pre-2000 engines requiring tensioner replacement before 150,000 km, while UK DVSA historic failure data links a significant portion of drivability complaints to idle control faults in poorly maintained examples. Extended oil intervals and use of non-specification lubricants increase wear rates, making oil quality and service adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (1997-2002) and UK DVSA historic failure statistics (2002-2010). Repair procedures should follow manufacturer guidelines.
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The M 112.945 is a robust engine when properly maintained, but pre-2000 models are prone to timing chain tensioner failure if oil changes are delayed or incorrect oil is used. Later revisions improved durability with a metal-backed tensioner. Regular servicing with correct 5W-40 API SL/CF oil and attention to the ME-SFI system are essential for long-term reliability.
The most common issues are timing chain tensioner wear, idle air control valve clogging, coolant leaks from the thermostat housing, and ignition coil degradation. These are documented in Mercedes-Benz service bulletins and technical forums. Preventive maintenance significantly reduces failure rates.
The M 112.945 was used in the W210 E 280, W202 C 280, and C208 CLK 280 models from 1997 to 2002. It was the 24-valve SOHC variant of the M112 engine family, distinguished from the earlier 18-valve versions used in other 280 models.
Limited tuning potential exists. Modifications include performance camshafts, upgraded intake manifolds, and ECU remapping. However, the engine's SOHC design limits high-RPM output. Most owners prioritize reliability over modification due to parts availability and classic status.
Fuel consumption is moderate for its era. In a W210 E 280, typical figures are ~12.5 L/100km (city) and ~7.5 L/100km (highway), or approximately 23 mpg UK combined. Driving style and vehicle condition significantly affect real-world economy, with well-maintained examples achieving up to 28 mpg UK.
Yes. The M 112.945 is an interference engine. If the timing chain fails or skips, pistons can contact open valves, resulting in severe internal damage. Regular inspection of the chain and tensioner is crucial, especially on high-mileage engines.
Mercedes-Benz specifies SAE 5W-40 oil meeting API SL/CF specifications. Use of correct oil is critical to protect the timing chain tensioner from premature wear. Oil should be changed every 15,000 km or annually, whichever comes first, to ensure adequate lubrication and cooling.
Comprehensive technical documentation and regulatory references
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DVLA: Engine Changes & MoT
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Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
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