Note. Separate characteristics are also given in the text of the Chapter and, if they are mandatory, are highlighted in bold.
Fuel grades
Petrol models
Unleaded gasoline is not worse than AI95 / A85. Short-term use of unleaded gasoline is allowed not worse than AI91 / A82.5 (the power developed by the engine decreases slightly, fuel consumption increases).
Attention! The use of fuel additives is fraught with premature wear and damage to internal engine components!
Diesel models
Summer and winter diesel fuel
Attention! Do not use ship, boiler, etc. diesel fuel!
Note. When using diesel fuel with increased (over 0.5%) sulfur content above, change the engine oil every 7500 km.
Winter fuel ensures normal engine performance at temperatures down to -20°C.
Thanks to the pre-heating of the fuel when the interior heating system is on, trouble-free operation of the engine is guaranteed at outdoor temperatures down to -25°C.
Attention! Do not mix gasoline with diesel fuel!
In the case of using summer diesel fuel, as well as at outside air temperatures below -15°C, a certain amount of flow improver or kerosene, depending on the outside temperature, must be added to the fuel.
Composition of the mixture
Outside temperature°C | -15 to -23 | -23 to -30 |
Summer diesel fuel | 80% | 50% |
Kerosene | 20% | 50% |
Outside temperature°C | -25 to -30 | -30 to -35 |
Winter diesel fuel | 80% | 50% |
Kerosene | 20% | 50% |
Flow improvers can also be used in combination with kerosene.
A certificate of approved flow improvers can be obtained from any Mercedes-Benz workshop.
The proportion of the additive content, taking into account the outside temperature, should be minimal.
The proportion of kerosene in the mixture should be no more than 50%.
The additive must be added to the fuel at the time of refueling before it thickens and releases paraffin. Faults due to waxing can only be eliminated by heating the entire power system.
Mix diesel fuel with kerosene only in the fuel tank - first, kerosene is poured into the tank, then diesel fuel is added. In conclusion, let the engine run for some time to distribute the mixture throughout the entire path of the power system.
Warning! Kerosene additives lower the flash point of the diesel fuel, which increases the fire hazard of the mixture! Observe the relevant safety regulations!
Fuel tank volume, l
Models without ski bag | |
Total capacity approx | 88 |
Including fuel reserve of approx | 11 |
Models with ski bag | |
Total capacity approx | 78 |
Including fuel reserve of approx | 10 |
Petrol injection system
System type | Electronic microprocessor distributed injection system. Inlet pipeline with variable geometry. |
S280 S320 | Bosch HFM |
S420, S500, S600 | Bosch LH or ME |
Diesel injection system
Type | Bosch injection pump, PES 6M RS 181, No. 0 400 076 956 with double chain drive from the crankshaft sprocket |
Injection moment | Installed using the control pin, the engine must be at TDC |
Regulator | № 0 400 076 956 |
Bosch injectors, | № 0 432 217 266 |
System pressure, bar | |
Fuel pump outlet (S500, S600) | 5.3-5.5 |
With vacuum off | 3.7-4.2 |
With connected vacuum | 3.2-3.6 |
On open nozzles (TDI) | |
New/Used | 115-125/100 |
Coolant temperature sensor resistance, Ohm (at a temperature) | |
S280, S320 | 309-341 (80°) |
S420, S500, S600 | 325 (80°) |
S300 TDI | Data not provided |
RPM/TDC sensor resistance, Ohm | |
S280, S320 | 680-1200 |
Injector resistance, Ohm | 14-16 |
Duration of opening of injectors, ms, at rpm | |
S280, S320 | 2.5-3.8, at 700 |
Adjustment data
Checking the installation of the injection start point of the injection pump
Crankshaft position marks when adjusting the injection pump 24° (EGR 19°) before TDC
Idle speed adjustment (TDI models)
idle speed (supported automatically) | |
S280, S320 | 650-800 |
S420, S500, S600 | 675±50 |
S300 TDI | 560-660 |
RPM limit without load | |
S300 TDI | 4600-4900 |
CO content at idle with oil heated to 60°C | Not more than 0.5% |
The content of the National Assembly at idle rpm, ppm (particles) | 100 |
CO2 content at idle | 14.5-16% |
O2 content at idle | 0.1-0.5% |
CO content at 2200-2800 rpm | 0.3% |
Lambda value at 2200-2800 rpm | 0.97-1.03 |
Adjusting position of injection pump (see illustration) | 24°before TDC |
Tightening force of threaded connections, Nm
Fastener tightening torques are also given in the text of the Chapter and in some illustrations *.
* The tightening torques shown in bold type must be strictly adhered to; Efforts not in bold type are indicative only.
Oxygen sensor | 50-60 |
Knock sensor | 20 |
CKP sensor mounting bolt | 10 |
CMP Sensor Mounting Bolt | 10 |
Fuel line connectors | 10-14 |