Damage patterns on lambda sensors
Due to their installation position, lambda sensor are subjected to high temperatures, aggressive chemicals and vibrations. Therefore, they are subject to wear and ageing. We recommend having the function checked every 30,000 km and/or on every exhaust emission check.
Possible malfunctions may be perceptible if the engine is running rough or fuel consumption increases. The workshop professional can determine definitively whether the lambda sensor is functioning properly. A visual inspection alone is not enough.
Bent sensor
The sensor was probably installed incorrectly and the signal transfer can be disrupted as a result. The sensor should be replaced.
Cable or plug melted
These damages result from contact with the exhaust system. The sensor must be replaced.
Carbon deposits
The protective tube exhibits heavy carbon deposits. This can arise from a mixture which is too rich, wear on the engine and valves or leakage in the exhaust system. Since the carbon deposits block the openings in the protective tube, the sensor can no longer work properly.
Rusty contacts
In this case emerging water has penetrated and causes the corrosion of the contacts. On replacement of the sensor, the seating of the plug as well as all connections between the sensor and engine control unit must be closely inspected.
Frayed/broken cables
The sensor was probably subjected to a heavy pulling effect. On replacement, ensure that the cable not routed too tightly.
Cable seal loosened
The sensor was probably routed too tightly. Water can penetrate. The sensor should be replaced.
White/grey deposits
Heavy white or grey deposits indicate that fuel additives are used or oil is being burnt. After remedy of the cause, the sensor must be replaced.
Heavy white or grey deposits indicate that fuel additives are used or the engine is burning oil
