NTK’s oxygen sensors under the spotlight
Niterra’s environmentally friendly credentials have been further supported by its NTK Vehicle Electronics brand and includes six product lines. All of its components contribute positively to the environment through measures that are helping to reduce engine emissions.
One of the key products offered by Niterra’s NTK Vehicle Electronics brand is the oxygen sensor, a vital piece of technology in engines that help to regulate its performance and ensure the optimal operation of the catalytic converter.
Niterra is one of the world’s largest suppliers of such sensors for OE customers, and among the leaders in servicing the Aftermarket. From an IAM perspective, Niterra offers a comprehensive range of high-quality sensors, and customers benefit from the same trusted quality that OEMs rely on, as Niterra manufactures its sensors in-house, ensuring consistent performance and reliability. With an extensive portfolio designed to meet the diverse needs of the Aftermarket, Niterra delivers dependable solutions that set the benchmark for IAM sensor quality.
In total, Niterra’s NTK brand offers 623 Aftermarket parts numbers that cover 63% of vehicles in operation in the EMEA region, which amount to 213 million vehicles and include 30 motorcycle parts numbers, with 6 universal parts numbers covering 62 million vehicles alone.
Essentially, the oxygen sensors within a vehicle operate by helping to ensure that the amount of harmful emissions released during an engine’s operations are kept to an absolute minimum. This is achieved by the sensors’ ability to measure the proportion of residual oxygen in a vehicle’s emissions. This information is then relayed back to the engine control unit (ECU), which can then adjust the air-fuel mixture to ensure that emissions are kept to the lowest level possible. They also have the additional advantage of helping to reduce an engine’s fuel consumption and also ensure increased longevity for the vehicle’s catalytic converter, an expensive item to repair or replace in any modern engine. The catalytic converter is responsible for converting dangerous particulate pollution from an engine’s emissions before they are expelled from the exhaust pipe.
A central part of engine efficiency
Within an engine, the optimum air-fuel mixture is known as the stoichiometric ratio and corresponds to a value of lambda 1, another reason the oxygen sensor is known as a lambda sensor. This ratio, although ideal, cannot be taken for granted and that is why the sensor’s monitoring is so key to a correctly functioning engine. If this blend of oxygen and fuel is too rich or too lean, the catalytic converter cannot do its job properly. This stoichiometric ratio is rated as 14.7kg air to 1kg fuel. In short, it is the job of the oxygen sensors to help the ECU maintain this air-fuel mixture as close as possible to this ratio and keep it there.
NTK Vehicle Electronics offers three types of oxygen sensor: zirconia sensors (which are also known as voltage jump sensors, binary sensors, or oxygen zirconia automotive sensors), titanium sensors (which are also called resistance jump sensors or titanium oxide sensors), and linear sensors (also referred to as broadband sensors).
The general rule is that each catalytic converter in a vehicle has two oxygen sensors to monitor emissions effectively. One sensor is known as the upstream unit and measures the emissions directly emanating from the engine. The other sensor is positioned downstream and is situated behind the catalytic converter. This sensor measures the oxygen in the exhaust after the catalytic conversion. The ECU receives data from both these oxygen sensors and uses it to optimize the air-fuel ratio and to work out the catalytic converter's overall performance, based on information from both the sensors combined.
The importance of sensor maintenance and timely replacement
Oxygen sensors are an effective part of emissions reduction. However, occasionally problems with sensors can occur. These often stem from contact with fuel additives, or silicon and carbon deposits. Usually, the first sign that something is wrong will be a warning light on the vehicle’s dashboard and increased fuel consumption, coupled with an engine that idles roughly and may stall. Failure to replace the faulty part immediately will have an impact on the vehicle’s fuel consumption, the amount of harmful emissions it emits, the catalytic converter, and ultimately, the overall health of the engine.
Thankfully, in the hands of a professional, replacing an oxygen sensor is a fast procedure that is fairly straightforward. Once the old unit has been removed and the new part has been screwed into place using the correct torque, an oscilloscope can then be applied to check if the sensor is working correctly.
This feature is one of a series that aims to offer technical information relating to a particular component from either the NGK Ignition Parts or NTK Vehicle Electronics brands from Niterra. This is the fourth in a sequence of such reports that are intended to highlight the different components from Niterra’s state-of-the art automotive products (previous articles in the series can be found under Niterra Feature - Insights and Background Information). The next subject under the spotlight will be exhaust gas temperature sensors (EGTS).
For further information on NTK oxygen sensors please visit TekniWiki, a technical platform that provides interactive learning modules that offers further insightful information on key engine components.