Walker 350-35005 Oxygen Sensor - Upstream

Walker 350-35005 Oxygen Sensor Overview

Walker Products 350-35005 is a heated oxygen sensor built as a specific-fit OE replacement for select Audi applications. It is engineered to provide the ECU with the exhaust feedback needed for fuel control and emissions monitoring, making it a direct choice for upstream sensor service on the listed vehicles.

Compatible with 2007 Audi A8 Quattro upstream cylinder 1-3 applications and 2007 Audi S8 upstream cylinder 1-3 applications, this sensor is designed around the original mounting position and connector style for accurate replacement fitment.

Key Features

• Heated oxygen sensor for faster operating temperature and signal response
• Specific-fit design for the listed Audi upstream applications
• 18.0 mm thread diameter with threaded mounting type
• 5-wire configuration with 20-gauge wiring
• 18.23 in. wiring harness length and 21.77 in. overall length
• Radiused polygon connector shape with male connector gender
• Walker Products Aftermarket line engineered for OE-style replacement use

Fitment and Application Details

Fits 2007 Audi A8 Quattro, upstream, cylinders 1-3, from chassis/VIN #4E7017 001.

Fits 2007 Audi S8, upstream, cylinders 1-3.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors developed for original-equipment replacement needs. Part number 350-35005 is built for the specified application and position so the ECU receives the correct diagnostic feedback for upstream exhaust monitoring. This part number, 350-35005, is also referenced for the same Audi fitment shown above.

What This Sensor Helps Address

• Check engine light related to upstream oxygen sensor performance
• Rough engine operation caused by incorrect air-fuel feedback
• Increased fuel consumption from inaccurate exhaust readings
• Elevated exhaust emissions from a failing sensor
• Fault codes stored in the ECU for the affected sensor circuit

Installation Notes

Verify the vehicle VIN and cylinder-bank application before ordering, especially on the 2007 Audi A8 Quattro where fitment begins from chassis/VIN #4E7017 001. Inspect the sensor wiring harness and connector for damage before installation, since damaged wiring can shorten sensor life and affect operation. Confirm the threaded mounting location and connector match the original sensor before replacement.

Quality Assurance

Walker Products is an Automotive ISO9001/TS 16949 certified company with a long history in engine management components dating back to 1946. The Walker Products Aftermarket line is built around application-specific sensor replacement for modern ECU-controlled vehicles.