Description

Set of 2 Bosch Oxygen O₂ Sensors – Audi A4 / & A4 Quattro 1.8L / 2.0L (2001–2020) This set of 2 new Bosch oxygen sensors is a direct-fit replacement for Audi A4 and A4 Quattro models (2001–2020) with 1.8L or 2.0L engines . Installed upstream and downstream, these sensors monitor exhaust oxygen levels and provide real-time data to the engine control module (ECM) to maintain optimal air-fuel mixture. Failing oxygen sensors can lead to poor fuel economy, rough idling, engine hesitation, increased emissions, and check engine lights . Replacing both sensors ensures balanced engine operation, restored fuel efficiency, and reliable emissions performance. Bosch sensors are built to OEM standards for long-lasting durability and precise response, even in high-temperature turbocharged engines. Key Features & Benefits Complete set of 2 Bosch oxygen (O₂) sensors Direct-fit replacement for Audi A4 & A4 Quattro 1.8L / 2.0L Accurate upstream and downstream oxygen monitoring Restores air-fuel ratio for optimal engine performance Improves fuel efficiency and throttle response Reduces harmful exhaust emissions Prevents check engine light recurrence High-temperature, durable construction Plug-and-play installation Engine Compatibility Audi 1.8L L4 Engine Audi 2.0L L4 Engine Vehicle Applications Audi A4 / A4 Quattro: 2001–2020 (1.8L & 2.0L Engines) Frequently Asked Questions – Bosch Oxygen Sensor Set for Audi A4 Why replace both oxygen sensors? Replacing both sensors ensures balanced readings, optimal air-fuel mixture, and consistent engine performance. Which Audi models does this set fit? This set fits 2001–2020 Audi A4 and A4 Quattro with 1.8L or 2.0L engines. What are the signs of a failing oxygen sensor? Symptoms include poor fuel economy, rough idle, engine hesitation, check engine light, and increased emissions. Are these Bosch sensors OEM quality? Yes, Bosch manufactures these sensors to meet or exceed OEM specifications for performance and durability. Is professional installation required? While the sensors are plug-and-play, professional installation is recommended for optimal placement and torque.