Bosch 16166 Oxygen Sensor - Downstream

Bosch Actual OE Oxygen Sensor 16166

Bosch 16166 is a specific-fit, narrow-band heated oxygen sensor for downstream applications on select Volkswagen and Audi models. It provides the ECU with precise air-fuel-ratio feedback to support stable closed-loop operation and emissions control.

Key Features

• Actual OE Oxygen Sensor from Bosch Actual OE Oxygen Sensor line
• Narrow-band heated O2 sensor with 4-wire, blade-terminal design
• Specific-fit threaded mounting with 18 mm thread diameter and 22 mm hex size
• Wiring harness included with oblong male connector
• Metal housing and high-temperature materials for demanding exhaust conditions
• Fits 2015-2023 Volkswagen and Audi downstream applications listed below

Product Details

Bosch developed its oxygen sensor technology from early thimble-style designs to later planar narrowband sensors that respond faster and reach operating temperature sooner. This Bosch 16166 sensor uses a heated narrow-band design to deliver accurate lambda feedback after startup and during normal driving, helping the engine control module maintain the correct air-fuel mixture. It is a direct replacement for downstream service on vehicles such as the Volkswagen Golf, GTI, Golf R, Golf SportWagen, Golf Alltrack, Atlas, and Atlas Cross Sport, plus Audi A3, S3, TT Quattro, and TTS Quattro. This part cross-references 8S0906262B for the same application.

Vehicle Fitment

• Fits 2018-2023 Volkswagen Atlas, downstream.
• Fits 2020-2023 Volkswagen Atlas Cross Sport, downstream.
• Fits 2017-2020 Audi A3, downstream.
• Fits 2017-2019 Volkswagen Golf Alltrack, downstream.
• Fits 2015-2019 Volkswagen Golf SportWagen, downstream.
• Fits 2015-2018 Audi S3, downstream.
• Fits 2018 Audi TT Quattro, downstream.
• Fits 2016-2018 Audi TTS Quattro, downstream.
• Fits 2015-2018 Volkswagen Golf, downstream.
• Fits 2018 Volkswagen Golf R, downstream, from 03/2018.
• Fits 2015-2018 Volkswagen GTI, downstream.
• Fits 2015-2017 Volkswagen Golf R, downstream.

Installation Notes

Verify the downstream sensor location, connector style, and thread size before installation. Use the 18 mm thread and 22 mm hex dimensions to confirm the correct removal tool, and inspect the harness routing so the lead length matches the original layout. Bosch 16166 is a direct-fit replacement for the listed Volkswagen and Audi applications, including Volkswagen Golf and Audi A3 service work.

Quality Assurance

Bosch backs this oxygen sensor with more than five decades of OE development and supplies aftermarket parts built to OE-proven standards. The sensor uses durable ceramic elements, controlled heater operation, and heat-resistant materials to maintain consistent signal quality under thermal and vibration load.