VW POLO Lambda sensor

Where can you find the lambda sensors in a Volkswagen Polo?

The location of these components depends on the engine type and the year of production. Most modern vehicles are fitted with two oxygen sensors. One of them is located in the exhaust manifold upstream of the catalytic converter and the second one downstream of it. This increases the measurement accuracy.

What are the types and how do they differ?

The following kinds of lambda sensors are available for Volkswagen Polo:

• Heated: these are the most common ones. They are three- and four-wire components that quickly heat up to the required temperature.
• Planar: these are made using zirconium dioxide and aluminium oxide. They are light and can heat up in 5-–30 seconds. They are also inexpensive.
• Titanium dioxide: these require a reference voltage to function. They are long lasting and highly accurate. However, they have a complex design and are expensive.
• Wideband: these are used in modern vehicles and have a wide measurement range. They can be four- or five-wire. They help ensure the correct air-–fuel ratio.

Can I install lambda sensors of different types in a Volkswagen Polo?

In some cases, when it is impossible to buy the required component, replacing it with a different one with similar characteristics is allowed. Please note that if your vehicle had a heated component, you cannot substitute it with an unheated one.

Replacing zirconium parts with titanium ones is not permitted either. They use different methods of measurement and data readout. Replacing one with the other could lead to poor engine performance.

What is the average service life of these components in this model? What are the most common causes of failure?

The service life of lambda sensors depends on an engine type and vehicle operating conditions. On average, components without a heating element last for 60,000–80,000 km, while heated last for 100,000 km. Planar sensors can cover a distance of 160,000 km. It is recommended to test the parts every 30,000 km.

These components can break down because of poor-quality fuel, a faulty ignition system, mechanical damage, and too much off-road driving. In addition, sensors fail if the oil-scraper piston rings wear out or antifreeze gets into the exhaust system.

What are the possible consequences of not changing lambda sensors in a Volkswagen Polo on time?

Driving a car with a faulty sensor leads to poor engine performance, increased fuel consumption, and poor dynamics. Exhaust emissions also increase, which is damaging to the environment.