NTK is the world's largest supplier and manufacturer of OEM oxygen sensors. Oxygen sensors play a critical role as part of the vehicle's on-board diagnostic system in maintaining optimal engine performance, maximizing fuel efficiency and reducing harmful emissions. Providing constant closed loop feedback to the ECU, oxygen sensors help to control the air-fuel ratio while alerting OBDII systems of possible problems with fuel delivery or catalytic converter efficiency. A ceramics company at our core, NTK uses state-of-the art technology enabling control of the ceramic element used in our oxygen sensors from raw material to finished product. Trust The Sensor Specialist for full-line market support and OE application technology. NTK is constantly improving sensor designs to provide excellent performance and improve resistance to failure. NTK works with their OEM manufacturers through each phase of development from concept to production.

ADVANCED CERAMIC SENSOR ELEMENT: 3-stage contaminant-resistant plasma jet and deposit trap overcoat protects against element poisoning

The NGK Audi A6 Quattro 1996-1998 Direct Fit Oxygen Sensor (Part Number 25643) is engineered to optimize your vehicle’s engine performance and fuel efficiency. Designed with advanced ceramic sensor elements, this sensor features a three-stage contaminant-resistant plasma jet and deposit trap overcoat that protects against element poisoning, ensuring long-lasting reliability. Proper functioning of this sensor is vital for maintaining the correct air-fuel ratio and providing accurate feedback to your vehicle’s ECU, which helps reduce harmful emissions and supports the vehicle’s on-board diagnostic system. It is compatible with multiple Audi models from 1996 to 1998, including the Audi A6 Quattro and A8 series, ensuring a precise fit and seamless integration into your vehicle’s exhaust system. Built to meet OE standards, this sensor undergoes rigorous testing and continuous improvements to resist failure and contamination, contributing to overall engine health and efficiency. Trust NGK’s expertise in sensor technology and OEM application support for your automotive needs. This oxygen sensor adheres to Prop 65 regulations and is designed for easy installation, providing a reliable solution for maintaining optimal vehicle performance. Please note that this product does not qualify for CARB exemptions, and acknowledgment of Prop 65 compliance is required during purchase. Whether you’re replacing a failing sensor or upgrading your vehicle’s emissions system, the NGK Audi A6 Quattro oxygen sensor offers durable performance and peace of mind for your automotive maintenance needs.

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