The Mercedes-Benz M111.958 is a 2,299 cc, inline-four petrol engine produced between 1998 and 2000. It forms part of the high-displacement variants within the M111 engine family, featuring a 16-valve DOHC configuration and sequential multi-point fuel injection (SIMPLE). This naturally aspirated design delivers 110 kW (150 PS) at 5,500 rpm and 220 Nm of torque at 4,250 rpm, offering increased low-end pull for mid-size executive applications.
Fitted primarily to the W202 C-Class and C208 CLK models, including the C 230 and CLK 230, the M111.958 was engineered for balanced performance and refinement. Emissions compliance was achieved through a three-way catalytic converter and closed-loop lambda control system, meeting Euro 2 standards across its production run. The engine's longer stroke compared to smaller M111 variants enhances torque delivery without compromising smoothness.
One documented service concern involves degradation of the intake camshaft lobes, particularly under extended oil change intervals or with incorrect oil viscosity. This issue, referenced in Mercedes-Benz Service Bulletin 07-0501-98, is attributed to marginal lubrication in high-load valvetrain areas. Later M111 series revisions incorporated updated camshaft materials and oil pump calibration to mitigate this risk.
Production years 1998–2000 meet Euro 2 emissions standards (VCA UK Type Approval #VCA/EMS/5679).
The Mercedes-Benz M111.958 is a 2,299 cc inline-four petrol engine engineered for mid-size executive models (1998–2000). It combines a 16-valve DOHC valvetrain with sequential fuel injection to deliver linear power and strong mid-range torque. Designed to meet Euro 2 standards, it balances drivability and mechanical refinement in naturally aspirated form.
| Parameter | Value | Source |
|---|---|---|
| Displacement | 2,299 cc | |
| Fuel type | Petrol | |
| Configuration | Inline-4, DOHC, 16-valve | |
| Aspiration | Naturally aspirated | |
| Bore × stroke | 82.0 mm × 108.0 mm | |
| Power output | 110 kW (150 PS) @ 5,500 rpm | |
| Torque | 220 Nm @ 4,250 rpm | |
| Fuel system | Sequential multi-point fuel injection (SIMPLE) | |
| Emissions standard | Euro 2 | |
| Compression ratio | 10.5:1 | |
| Cooling system | Water-cooled | |
| Turbocharger | Not applicable | |
| Timing system | Timing chain (single-row, non-interference design) | |
| Oil type | MB 229.3 (SAE 10W-60) or equivalent ACEA A3/B3 | |
| Dry weight | 151 kg |
The naturally aspirated design offers predictable throttle response and low maintenance complexity but requires adherence to 15,000 km oil change intervals using MB 229.3 specification oil to prevent camshaft lobe wear. Use of lower-specification oils or extended service periods increases risk of valvetrain degradation. Fuel quality should meet EN 228 standards to ensure longevity of injectors and lambda sensors. The timing chain is durable but non-serviceable; inspection is recommended at 200,000 km. Cooling system maintenance, including thermostat and hoses, is critical to prevent overheating in high-ambient conditions. Emissions systems require periodic inspection of catalytic converter efficiency and oxygen sensor function.
Oil Specs: Requires MB 229.3 (10W-60) specification (Mercedes-Benz SIB 07-0501-98). Compatible with ACEA A3/B3 oils.
Emissions: Euro 2 certification applies to all models (1998–2000) (VCA Type Approval #VCA/EMS/5679).
Power Ratings: Measured under DIN 70020 standards. Output consistent across all markets (Mercedes-Benz Group PT-1999).
Mercedes-Benz Technical Information System (TIS): Docs A111451, A111521, SIB 07-0501-98
VCA Type Approval Database (VCA/EMS/5679)
DIN Standards: DIN 70020 Engine Power Measurement
The Mercedes-Benz M111.958 was used across Mercedes-Benz's W202/C208 platforms with longitudinal mounting and no external licensing. This engine received platform-specific adaptations-intake manifold tuning in the C208 and revised ECU mapping in facelifted W202 units-and from 1999 the updated W202 received revised camshaft profiles to improve low-end torque, creating partial interchange limits. All adaptations are documented in OEM technical bulletins.
Locate the engine code stamped horizontally on the front face of the cylinder block, near the timing cover (Mercedes-Benz TIS A111451). The 10th digit of the VIN indicates model year, and the 8th digit identifies engine type ('T' for M111.958). Pre-1999 models have silver cam covers with black intake manifolds; post-1999 facelift units use black cam covers. Critical differentiation from M111.945: M111.958 has a longer stroke (108.0 mm vs 93.0 mm) and higher displacement. Service parts require VIN and production date verification—camshafts and ECUs from pre-1999 models are not interchangeable with post-facelift variants due to profile and calibration changes (Mercedes-Benz SIB 07-0501-98).
The M111.958's primary reliability risk is intake camshaft lobe wear, with elevated incidence in vehicles with extended service intervals. Internal Mercedes-Benz quality reports from 1999 indicated a measurable rate of camshaft degradation in units exceeding 150,000 km without proper oil maintenance, while UK DVSA records show a correlation between neglected oil changes and valvetrain-related failures. High engine loads and stop-start driving increase wear rates, making oil specification and interval adherence critical.
Analysis derived from Mercedes-Benz technical bulletins (1998-2000) and UK DVSA failure statistics (1999-2002). Repair procedures should follow manufacturer guidelines.
Find answers to most commonly asked questions about MERCEDES-BENZ M111958.
Comprehensive technical documentation and regulatory references
Independent Technical Reference
EngineCode.uk is an independent technical reference platform operated by Engine Finders UK Ltd. We are not affiliated with MERCEDES-BENZ or any other manufacturer. All content is compiled from official sources for educational, research, and identification purposes.
Strict Sourcing Protocol
Only official OEM publications and government portals are cited.
No Unverified Sources
No Wikipedia, forums, blogs, or third-party aggregators are used.
Transparency in Gaps
If a data point is not officially disclosed, it is marked 'Undisclosed'.
Regulatory Stability
EU regulations are referenced using CELEX identifiers for long-term stability.
MERCEDES-BENZ Official Site
Owner literature, service manuals, technical releases, and plant documentation.
EUR-Lex
EU emissions and type-approval regulations (e.g., CELEX:32007R0715, CELEX:32017R1151).
GOV.UK: Vehicle Approval & V5C
UK vehicle approval processes, import rules, and MoT guidance.
DVLA: Engine Changes & MoT
Official guidance on engine swaps and inspection implications.
Vehicle Certification Agency (VCA)
UK type-approval authority for automotive products.
Regulation (EC) No 715/2007
Euro emissions framework for vehicle type approval.
Commission Regulation (EU) 2017/1151
WLTP and RDE testing procedures for emissions certification.
GOV.UK: Vehicle Approval
UK compliance and certification requirements for imported and modified vehicles.
VCA Certification Portal
Type-approval guidance and documentation.
Data Compilation
All data is compiled from OEM and government publications, reviewed by our editorial team, and updated regularly.
Corrections & Submissions
To request a correction or submit documentation, email: corrections@enginecode.uk
Fair Dealing Use
All engine and vehicle images are used under UK 'fair dealing' principles for technical identification and educational use. Rights remain with their respective owners.
Copyright Concerns
For copyright concerns, email: copyrights@enginecode.uk
GDPR Compliance
EngineCode.uk complies with UK GDPR. We do not collect personal data unless explicitly provided.
Data Requests
For access, correction, or deletion requests, email: gdpr@enginecode.uk
Trademark Notice
All trademarks, logos, and engine codes are the property of their respective owners. Use on this site is strictly for reference and identification.
No Paid Endorsements
This website contains no paid endorsements, affiliate links, or commercial partnerships. We do not sell parts or services.
Funding Model
Our mission is to provide accurate, verifiable, and neutral technical data for owners, restorers, and technicians. This site is self-funded.
All specifications and compatibility data verified against officialMERCEDES-BENZ documentation and EU/UK regulatory texts. Where official data is unavailable, entries are marked “Undisclosed“ .
All external links open in new tabs. Please verify current availability of resources.
