Mercedes Benz Workshop Service and Repair Manuals

Oxygen Sensor: Electrical Specifications

Oxygen Sensor Heater Resistance................................................................................................................................................3 ohms (cold) 13 ohms (hot)
Oxygen Sensor Operating Voltage (engine running)...........................................................................................................................................0.4 - 1.0 volts
Oxygen Sensor Heating Element current draw.........................................................................................................................................................0.5 - 1.3 A

Tune-up Specifications

Firing Order............................................................................................................................................................................................................1-5-3-6-2-4
Idle Speed.......................................................................................................................................................................650-750 RPM [1] 550-650 RPM [2] 
Timing............................................................................................................................................................................................................0 ±2° BTDC [3] 
Air/fuel Mixture....................................................................................................................................................................................Readout oscillating [4]

[1] Manual Transmission
[2] Automatic Transmission in Drive
[3] Reference figure at cranking speed only, not adjustable
[4] At Diagnostic socket, with on/off ratio tester, and O2 sensor connected