Due to the hostile environment in which they work sensors are subject to a degree of wear and tear and ageing. It would be impossible to say definitively what the service life of a lambda sensor should be due to the very different conditions that each vehicle experiences under different drivers. It would be reasonable to expect that the service life of a lambda sensor fitted to a vehicle used mostly for short in-town journeys would be shorter than one used for steady motorway use. We recommend that the function of the sensor is checked every 20,000 miles or annually. The emissions check as part of the current M.O.T. test samples the exhaust gases to monitor the efficiency of the engine, exhaust system and engine control systems. A lambda sensor is a vital part of this system.

A worn, faulty or failed sensor might make itself apparent by causing the engine to run poorly, increasing fuel consumption, increasing unwanted exhaust emissions or illuminating a malfunction indicator lamp on the dashboard. Newer vehicles have the ability to store fault codes in the processor some of which will relate to the lambda sensor and associated systems. Defective sensors can also cause irreparable damage to the catalyst. Sensors (this includes the wiring harness and connector) that have sustained physical damage will most likely have their life shortened or performance affected and should also be renewed.