HOW OXYGEN SENSORS WORK
Common faults to look out for
For most of us, Oxygen sensors (also known as a Lambda or O2 sensor) are a little bit 'out of sight, out of mind'.
However, the oxygen sensor is vital part of the overall vehicles emissions control system and it's main job is to ensure the engine runs as efficiently as possible (based on an optimum fuel to oxygen ratio) while producing the lowest emissions.
Most vehicles manufactured after 1980 have at least one and new cars now come with two or more sensors further increasing the efficiency of the engine. They are located in the exhaust system, either before or after the catalytic converter which is an exhaust emission control (EEC) component.
The catalytic converter lowers (converts) the levels of toxic pollutants in the exhaust gas, a critical function to limit vehicle produced emissions.
Check out our Top 3 failure signs that may help you diagnose a bad Oxygen Sensor as well as some general performance tips worth keeping an eye on.
Everything you need to know about Oxygen Sensors
Three of the most common signs that your Oxygen Sensor may need replacing are:
1. A sudden drop in your Fuel economy as your engine may run too rich, in turn using more fuel.
2. The check engine light is illuminated. There could be various reasons, however a faulty Oxygen sensor is one of them.
3. The engine idles roughly, is sluggish or less responsive. Engine performance has many influences including a bad O2 sensor so worth checking.
Service intervals may change between manufacturers though as a basic guide:
1. Unheated 1 or 2 wire oxygen sensors have a typical service life of 50,000 kilometres.
2. Heated 3 or 4 wire oxygen sensors have a typical service life of 80,000 kilometres.
3. Planar oxygen sensors have a typical service life of 150,000 kilometres.
Types of vehicles with Oxygen sensors:
1. Vehicles manufactured from 1980 with a single exhaust (one catalytic converter) have at least one sensor.
2. Vehicles manufactured from mid-1990 with a single exhaust (one catalytic converter) came with two sensors. One is upstream of the catalytic converter and the other is downstream.
3. Vehicles with dual exhausts (two catalytic converters) come with four sensors. Both one upstream and downstream of each converter.
Aside from checking the function of your O2 sensor(s), here's a few additional things worth checking that can significantly effect your performance:
1. Is your Engine Air Filter clean and debris free?
2. Are your Spark Plugs functioning correctly?
3. Are you using the recommended fuel octane rating for your vehicle?
