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103.941 MERCEDES-BENZ Petrol 1985-1991

103.941 engine — Mercedes-Benz 2.6 (2.6L)

2.6L · 166 hp

Engine overview

Manufacturer
MERCEDES-BENZ
Displacement
2.6 L
Power
166 hp
Production years
1985-1991
Fuel type
Petrol

Vehicles with this engine

W126

Factory specifications

Values from the manufacturer documentation for this engine.

Engine (general)

Engine code 103.941
Capacity 2599 cc
Idle speed 650 - 750 rpm
Normal 10.0 - 12.0 bar
Minimum 8.5 bar
Oil pressure 0.9 / 750 2.0 / 1000 4.3 / 2000 4.6 / 3000 4.8 / 4000 5.0 / 5000 bar/rpm

Engine (petrol)

Fuel system (make and type) Bosch KE-Jetronic
Number of cylinders 6
Firing order 1-5-3-6-2-4
Timing stroboscopic (before TDC) 19 - 23 / 3200 °/rpm
Timing stroboscopic (vacuum hose connected) 40 - 44 / 3200 °/rpm
Timing stroboscopic (before TDC) 25 - 29 / 3200 °/rpm
Ignition coil resistance, primary 0.3 - 0.6 ohms
Ignition coil resistance, secondary 8000 - 13000 ohms
Spark plugs (make and type) Beru 14 K-8 DU Beru 14 K-8 DUO Bosch H 8 DC Bosch H 8 DCO Champion S 12 YC Champion S 12 YCC
Spark plug gap 0.8 mm
Injection pressure/system pressure 5.3 - 5.5 bar
CO exhaust gas 0.5 - 1.5 %
CO2 13.0 - 16.0 %
HC 300 ppm
O2 0.5 - 2.0 %
CO at fast-idle speed < 0.3 %
Fast-idle speed 2200 - 2800 rpm
Lambda 0.97 - 1.03
Lambda change (Delta Lambda) 0.02
Oil temperature during test 60 °C
Closed-loop test at: 500 - 1100 rpm

Cooling system

Cap pressure 120: 1.2 ± 0.1 140: 1.4 ± 0.1 bar
Thermostat opens at 87 ± 2 °C

Electrical

Battery 62 Ah
Alternator 80 A

Capacities

Engine sump, incl. filter 6.0 l
Gearbox refill 1.5 l
Differential 1.0 l
Gearbox refill 6.0 l
Gearbox refill after overhaul 7.1 l
Cooling system 8.0 l

Torque settings

Cylinder head bolts — Stage 1 70 Nm
Cylinder head bolts — Stage 2 90 °
Cylinder head bolts — Stage 3 90 °
Spark plugs 20 Nm
Automatic transmission drain plug 22 Nm
Manual transmission filler plug 60 Nm
Manual transmission drain plug 60 Nm
Wheel nuts 110 Nm
Rear hub 30 Nm
Rear hub 90 Nm

Workshop procedures for this engine

Step-by-step procedures from the workshop database.

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Who makes these pages, and how

TorqFix was built by a mechanic — after a 2,700 km drive with five roadside repairs that no diagnostic tool could explain.

The figures on this page come from manufacturer workshop documentation and are shown as they are. The page is assembled automatically from that data — it is not written by an AI. The AI works in the chat, where it answers for your specific car. It writes nothing here.

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Workshop data on this page last updated 22 Aug 2026.