Understand the role of the Lambda probe in the economy and cleaning of the engine

Indispensable in the electronic injection system, Oxygen Sensor (lambda probe) measures the amount of residual oxygen in the exhaust gas and ensures lower environmental impact

São Paulo, June 2025 - The search for more efficient and environmentally responsible vehicles has been a constant concern for automakers, which focuses on reducing pollutant emissions. In Brazil, The regulation of gas emissions and monitoring of improvements in the environmental impacts caused by cars is carried out by the National Environmental Council (Conama), through the Air Pollution Control Program from Motor Vehicles (Proconve), which establishes progressive limits on vehicle emissions - especially carbon monoxide (CO), nitrogen oxides (NOx) and hydrocarbons (HC) - and sets reduction targets.

Within this regulatory context, Proconve has adopted the imposition of increasingly strict limits in relation to gas emissions, by vehicles in circulation - the most recent update to the standard is from January 2022. To meet the agency's requirements and the proper functioning of technological components in automobiles they have become even more relevant. An example is the lambda probe, also known as oxygen sensor, which plays a fundamental role in controlling and reducing pollutant emissions. In order to make drivers aware of its importance, The NAT, brand of Niterra, Japanese multinational company that also owns the NGK brand, highlights the benefits that this part offers both for drivability and the environment.

1- Combustion optimization: the lambda probe provides precise information to the electronic injection system about the burning of the air/fuel mixture. Based on this sign, the system continuously adjusts the mixture to ensure more efficient and cleaner combustion.

2. Reduction of polluting emissions: correct probe reading allows the catalysts to operate within the best air/fuel mixture conditions. This component is responsible for converting harmful gases into less polluting substances. This significantly contributes to reducing the release of polluting gases.

3. Catalyst efficiency monitoring: the oxygen sensor when installed in the post catalyst position, allows evaluation, whether the catalytic converter is operating efficiently. If there is a loss of efficiency, the system activates the warning lamp (LIM), indicating a possible problem with the vehicle, alerting the driver to the need for an inspection to check for possible repairs, and thus maintain the correct emission levels for which the vehicle was approved.

4. Preventing vehicle damage: going beyond emissions issues, a malfunctioning probe can affect engine performance, which may cause an increase in fuel consumption, misfires and reduce the useful life of components such as spark plugs and catalysts.

“When there are faults in the lambda probe, indicated by the electronic injection light coming on (LIM) on the panel, impacts can be significant. Increased fuel consumption is just one of the problems that can occur”, alerta Hiromori Mori, Niterra Technical Assistance Consultant. "Furthermore, the driver may notice the accumulation of residues in the combustion chamber in case of a rich mixture and even a reduction in the useful life of the spark plugs and catalytic converter, due to contamination. In the case of a poor mixture, Damage to valves and pistons may occur, misfires and irregular engine operation.”

If the driver identifies these signs, It is highly recommended that you have the injection system evaluated by a trusted mechanic.. The lambda sensor must undergo annual tests and, if any failure is detected, replacement with a new part must be immediate. In this context, Drivers can count on a wide selection of high-tech and quality lambda sensors from the NTK brand, Available in the aftermarket.

Most modern vehicles use a linear or broadband type oxygen sensor, This sensor is highly technological and allows an extremely accurate reading of the condition of the air/fuel mixture that was burned. Its operation has a different concept from conventional probes and a different diagnostic strategy. Niterra do Brasil offers technical support to mechanics for the correct diagnosis of oxygen sensors through its SAC 0800 019 7112.