Walker 250-21011 Oxygen Sensor - Upstream

Walker Products OE Oxygen Sensor for Upstream Use

Walker Products OE Part Number 250-21011 is a specific-fit upstream oxygen sensor engineered for older import applications that rely on accurate exhaust feedback to the ECU. It is built for vehicles such as Audi 4000, Volkswagen Jetta, and Jaguar XJ6 where the upstream sensor position is critical for fuel control and emissions monitoring.

Key Features

• Specific-fit upstream oxygen sensor for targeted vehicle applications
• Non-heated sensor design with threaded mounting
• Radiused polygon female connector for direct replacement fitment
• 20-gauge wiring with 20.0 wiring harness length
• 18.0 thread diameter and 23.54 overall length
• Walker Products OE line replacement for engine management and oxygen sensor service

Product Details

Walker Products OE 250-21011 is designed as an OE-style replacement oxygen sensor for upstream locations where the ECU depends on precise exhaust-gas feedback. The sensor supports applications across Audi, Volkswagen, Subaru, Nissan, Jaguar, Saab, Volvo, and related models listed in the fitment data, including 1985-1987 Volkswagen Golf, 1985-1987 Volkswagen Jetta, and 1980-1985 Jaguar XJ6. This part number 250-21011 is built for the specified position and connector style so the replacement matches the original sensor layout more closely.

Walker Products OE focuses on engine management sensors developed for application-specific fitment and diagnostic feedback. For vehicles with stored fault codes, a failing upstream oxygen sensor can contribute to poor running condition, higher fuel use, increased exhaust emissions, and a malfunction indicator light. The sensor, wiring harness, and connector should be inspected for damage during diagnosis.

What This Oxygen Sensor Helps Address

• Check engine or malfunction indicator light related to upstream oxygen sensor performance
• Rough engine operation caused by incorrect exhaust feedback
• Increased fuel consumption from inaccurate air-fuel correction
• Elevated exhaust emissions from a degraded sensor signal
• Fault codes tied to Bank 1 Sensor 1 or front oxygen sensor locations

Installation Notes and Tips

Confirm the vehicle’s sensor position before ordering, since this part is for upstream applications only. Verify connector shape, thread diameter, and harness length against the original sensor, and inspect the wiring and connector for heat damage or corrosion before installation. On vehicles such as Audi 4000 Quattro, Volkswagen Cabriolet, and Nissan D21, matching the exact upstream location is important for proper ECU feedback.

Quality Assurance

Walker Products is an automotive ISO 9001/TS 16949 certified company with a long history in engine management components. The Walker Products OE line is developed as an original-equipment-style replacement for specific vehicle applications, and part number 250-21011 follows that application-focused approach for consistent sensor feedback.