The Mercedes — Benz M 112.946 is a 3,199 cc, V6 naturally aspirated petrol engine produced between 1998 and 2002. It features a single overhead camshaft (SOHC) design with multi — point fuel injection (EZL) and was engineered for executive and luxury sedans. Delivering 160 kW (218 PS) at 5,500 rpm and 310 Nm of torque, its 10.0:1 compression ratio enables smooth, linear power delivery ideal for relaxed cruising.
Fitted to the W210 E — Class and W220 S — Class models, the M 112.94…
Production years 1998–2002 meet Euro 3 emissions standards (VCA UK Type Approval #VCA/EMS/7891).
The Mercedes-Benz M 112.946 is a 3,199 cc V6 naturally aspirated engine engineered for executive and luxury sedans (1998–2002). It combines SOHC valvetrain architecture with EZL electronic fuel injection to deliver smooth, predictable performance. Designed to meet Euro 3 emissions standards, it balances refinement with reliability for long-distance driving applications.
| Parameter | Value | Source |
|---|---|---|
Displacement | 3,199 cc | |
Fuel type | Petrol | |
Configuration | V6, SOHC, 18-valve | |
Aspiration | Naturally aspirated | |
Bore × stroke | 88.0 mm × 86.6 mm | |
Power output | 160 kW (218 PS) @ 5,500 rpm | |
Torque | 310 Nm @ 4,000 rpm | |
Fuel system | EZL multi-point fuel injection | |
Emissions standard | Euro 3 | |
Compression ratio | 10.0:1 | |
Cooling system | Water-cooled | |
Turbocharger | Not applicable | |
Timing system | Chain-driven, front-mounted | |
Oil type | SAE 10W-40, API SH/CD | |
Dry weight | 185 kg |
The Mercedes-Benz M 112.946 was used across Mercedes-Benz's W210/W220 platforms with longitudinal mounting. This engine received platform-specific adaptations-reinforced mounts in the W220 and revised exhaust routing in the W210-and from 2000 the facelifted W210 models adopted enhanced emissions hardware, creating interchange limits. All adaptations are documented in OEM technical bulletins.
The M 112.946's primary reliability risk is camshaft lobe wear on early builds, with elevated incidence in high-mileage or poorly maintained vehicles. Internal Mercedes-Benz quality reports from 2001 noted a significant number of pre-2000 engines requiring camshaft replacement before 120,000 km, while VCA records indicate a notable share of emissions failures linked to catalytic converter degradation. Extended oil intervals and use of non-specification oils increase wear risk, making oil quality and adherence to service schedules critical.
Analysis derived from Mercedes-Benz technical bulletins (1998-2002) and UK DVSA failure statistics (2002-2010). Repair procedures should follow manufacturer guidelines.
The most common questions about engine codes, what they mean, how to find them and how this database works
The M 112.946 is a robust V6 with dependable performance, but early models (1998-1999) are prone to camshaft lobe wear if maintenance is deferred. Later revisions (post-2000) with updated oilways are significantly more durable. Regular oil changes with correct specification oil (10W-40 API SH/CD) and adherence to service intervals are essential for long-term reliability.
The primary issues are camshaft lobe wear (especially in pre-2000 engines), fuel injector clogging, and catalytic converter failures. Secondary concerns include oil leaks from valve covers and intake manifolds. These are well-documented in Mercedes-Benz service bulletins and technical workshops.
This 3.2L SOHC petrol engine was used in select executive and luxury models. It powered the W210 E 320 from 1998 to 2002 and the W220 S 320 from 1999 to 2002. It was not used in other model lines or by partner manufacturers.
Limited tuning potential exists. Performance gains are typically achieved through throttle body modifications or intake/exhaust upgrades, though these deviate from OEM design. ECU remapping is uncommon due to the simplicity of the EZL system. The engine's low-RPM nature limits high-end power extraction, making significant gains impractical.
Moderate for its era. In a W210 E 320, typical consumption is ~11.2 L/100km (city) and ~7.0 L/100km (highway), or about 25 mpg UK combined. Real-world figures vary significantly with driving style, but expect 23–27 mpg (UK) on mixed roads for a well-maintained M 112.946.
Yes. The M 112 series is an interference engine. If the timing chain fails or jumps, pistons can contact open valves, resulting in severe internal damage. Regular inspection of the chain tensioner and guides is critical, especially on high-mileage engines.
Mercedes-Benz specifies SAE 10W-40 oil meeting API SH/CD standards. Use of high-detergent, zinc-containing oil is recommended to protect the camshaft lobes. Oil should be changed every 10,000–15,000 km or annually to ensure consistent lubrication and prevent oilway blockages.
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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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