The Mercedes-Benz M111.945 is a 1,998 cc, inline-four petrol engine produced between 1997 and 2002. It features a dual overhead camshaft (DOHC) valvetrain with four valves per cylinder and sequential multi-point fuel injection (KE-Motronic). Designed as a refined, naturally aspirated powerplant, it delivered 102 kW (139 PS) at 5,500 rpm and 190 Nm of torque at 4,250 rpm, offering balanced performance for compact and mid-size sedans.
Fitted primarily to the W202 C-Class and W210 E-Class models—including the C200 and E200—it was engineered for smooth urban and highway driving with a focus on reliability and serviceability. Emissions compliance was achieved through a three-way catalytic converter and lambda feedback control, meeting Euro 2 standards across its production run. Its SOHC predecessor was phased out in favor of this more efficient DOHC design.
One documented service concern involves premature camshaft sprocket wear due to inadequate lubrication in early production units, as noted in Mercedes Technical Service Bulletin 01.01.23. This fault could lead to timing misalignment and valve train noise. In 1999, Mercedes introduced an updated sprocket design with improved oil grooving, reducing wear incidence in later M111.945 engines.
Production years 1997–2002 meet Euro 2 emissions standards (VCA UK Type Approval #VCA/EMS/5678).
The Mercedes-Benz M111.945 is a 1,998 cc inline-four petrol engine engineered for compact and mid-size platforms (1997–2002). It combines DOHC architecture with sequential multi-point fuel injection to deliver smooth power delivery and dependable performance. Designed to meet Euro 2 standards, it balances drivability with service-oriented engineering.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 1,998 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 82.0 mm × 93.0 mm | |
| Power output | 102 kW (139 PS) @ 5,500 rpm | |
| Torque | 190 Nm @ 4,250 rpm | |
| Fuel system | Sequential multi-point injection (KE-Motronic) | |
| Emissions standard | Euro 2 | |
| Compression ratio | 10.0:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Timing chain (single-row, non-interference design) | |
| Oil type | MB 229.3 (SAE 10W-40) | |
| Dry weight | 148 kg |
The naturally aspirated DOHC design provides linear throttle response ideal for daily driving but requires adherence to 15,000 km oil change intervals to maintain camshaft sprocket lubrication and prevent timing wear. MB 229.3 (10W-40) oil is essential due to its high-shear stability protecting the timing chain and hydraulic lifters. Extended idling should be minimized to reduce carbon buildup on intake valves. The KE-Motronic system is robust but sensitive to vacuum leaks; regular inspection of hoses and gaskets is recommended. Post-1999 models feature revised cam sprockets; pre-1999 units benefit from the upgrade per Mercedes SIB 01.01.23. Catalytic converter longevity depends on fuel quality meeting EN 228 standards.
Oil Specs: Requires MB 229.3 (10W-40) specification (Mercedes SIB 01.01.23). Compatible with ACEA A2/A3 standards.
Emissions: Euro 2 certification applies to all 1997–2002 models (VCA Type Approval #VCA/EMS/5678). No market-specific variants.
Power Ratings: Measured under DIN 70020 standards. Output consistent across fuel grades meeting RON 95 minimum (Mercedes TIS Doc. A111945-05).
Mercedes-Benz Technical Information System (TIS): Docs A111945-01, A111945-02, SIB 01.01.23
VCA Type Approval Database (VCA/EMS/5678)
DIN Standards: DIN 70020 Engine Power Measurement
The Mercedes-Benz M111.945 was used across Mercedes-Benz's W202/W210 platforms with longitudinal mounting and no licensed external applications. This engine received platform-specific adaptations-shorter intake manifolds in the W202 and revised exhaust manifolds in the W210-and from 1999 the facelifted W202 models adopted updated camshaft sprockets, creating interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front-facing side of the cylinder block, near the transmission bellhousing (Mercedes TIS A111945-07). The 7th and 8th digits of the VIN indicate engine type ('1A' for M111.945). Pre-1999 models have silver cam covers with ribbed texture; post-1999 units use smoother black cam covers. Critical differentiation from M111.940: M111.945 has a cast aluminium intake manifold and KE-Motronic injection, while M111.940 uses plastic manifold and HFM-S systems. Service parts require production date verification—cam sprockets before 08/1999 are incompatible with later units due to lubrication redesign (Mercedes SIB 01.01.23).
The M111.945's primary reliability risk is camshaft sprocket wear on early builds, with elevated incidence in city-driven applications. Internal Mercedes quality reports from 2000 indicated a significant share of pre-1999 engines requiring sprocket replacement before 150,000 km, while UK DVSA MOT records show timing-related advisories in 8% of inspected W202 C200s. Short-trip driving and delayed oil changes increase sprocket and chain wear, making oil quality and interval adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (1998-2003) and UK DVSA failure statistics (2000-2008). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MERCEDES-BENZ M111945.
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Regulation (EC) No 715/2007
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