Walker 350-35050 Oxygen Sensor - Upstream

Walker Products 350-35050 Oxygen Sensor

Walker Products 350-35050 is a heated upstream oxygen sensor built as a specific-fit OE replacement for select Volkswagen and Audi applications. It is engineered to provide the ECU with the feedback needed for fuel control and emissions monitoring, making it a direct replacement for a failing front oxygen sensor.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for exact application fitment. The 350-35050 follows that approach with a threaded mounting design, 5-wire heated construction, and connector and harness dimensions matched to the listed vehicle applications.

Key Features

• Specific-fit heated oxygen sensor for upstream installation
• Threaded mounting type with 18.0 mm thread diameter
• 5-wire design with 20-gauge wiring
• Wiring harness length: 22.63
• Overall length: 27.55
• Male connector with radiused polygon connector shape
• OE-style replacement for ECU feedback on emissions and fuel management
• Walker Products 350-35050 part number for application matching

Detailed Description

The Walker Products 350-35050 oxygen sensor is designed for upstream placement where the engine management system monitors exhaust oxygen content before the catalytic converter. On listed Volkswagen Golf, Golf Alltrack, Golf SportWagen, GTI, and Audi A1, A3, A4, A4 Quattro, and A5 applications, this sensor supports the ECU with the signal needed for air-fuel correction and emissions control. If the original sensor is slow, contaminated, or electrically damaged, the vehicle may store fault codes and show drivability or efficiency concerns.

Use the 350-35050 when replacing a Bank 1 Sensor 1 or front oxygen sensor on the confirmed fitment list. This Walker Products oxygen sensor is built for the specified position and connector style, helping maintain proper sensor feedback on compatible Volkswagen Golf and Audi A3 applications, along with other listed models.

What It Helps Address

• Check engine light related to upstream oxygen sensor faults
• Poor engine performance from incorrect air-fuel feedback
• Increased fuel consumption caused by inaccurate sensor readings
• Higher exhaust emissions from a failing front oxygen sensor
• Stored ECU fault codes tied to the affected sensor circuit

Installation Notes and Tips

• Confirm the vehicle uses an upstream, Bank 1 Sensor 1, or front oxygen sensor position before ordering.
• Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion before installation.
• Verify thread diameter and connector style match the original part on the vehicle.
• Clear diagnostic trouble codes after installation and confirm the repair with a scan tool.
• Check for exhaust leaks or related engine management issues that can affect sensor readings.

Quality Assurance

Walker Products manufactures engine management sensors as OE-replacement parts for specific applications and positions. The brand states its sensor programs are developed under Automotive ISO9001/TS 16949 quality systems and backed by long-running experience in fuel system and sensor components.

• Fits 2017-2019 Volkswagen Golf Alltrack, upstream
• Fits 2015-2019 Volkswagen Golf SportWagen, upstream
• Fits 2019 Volkswagen GTI, upstream
• Fits 2015-2018 Volkswagen Golf, upstream
• Fits 2017 Volkswagen Polo, upstream
• Fits 2016-2018 Audi A1, upstream
• Fits 2015-2016 Audi A3, upstream
• Fits 2013-2016 Audi A4, upstream
• Fits 2012-2016 Audi A5, upstream
• Fits 2013 Audi A4 Quattro, upstream