Walker 350-35041 Oxygen Sensor - Upstream, Upstream Left or Upstream Right

Walker 350-35041 Oxygen Sensor Overview

Walker Products 350-35041 is a heated oxygen sensor built as a specific-fit OE replacement for select Audi, BMW, Buick, and Volkswagen applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper fuel control and emissions performance on the correct upstream position.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for exact application fitment. For vehicles such as the Buick Allure, Buick LaCrosse, and Audi A8 Quattro, the 350-35041 is matched to the listed bank, cylinder, and side requirements for accurate replacement service.

Key Features

• Heated oxygen sensor for faster operating response
• Specific-fit design for the listed vehicle applications
• Threaded mounting type with 18.0 mm thread diameter
• 5-wire configuration with 20-gauge wiring
• Radiused polygon male connector for application-specific connection
• Wiring harness length: 21.18 in.; overall length: 24.72 in.

Detailed Product Description

The Walker Products 350-35041 oxygen sensor is designed for upstream installation where the engine management system relies on precise exhaust feedback to adjust air-fuel ratio. This part number is listed for 2002-2008 applications including Buick Allure, Buick LaCrosse, Buick Rendezvous, Audi A8 Quattro, Audi Allroad Quattro, Audi S3, BMW 545i, BMW 645Ci, BMW 745i, BMW 745Li, BMW X5, and Volkswagen Touareg. It is also a direct replacement for the specified upstream right and upstream left positions shown in the fitment data.

As an OE-style replacement from Walker Products Aftermarket, part number 350-35041 is built for the exact sensor location and ECU feedback requirements of the application. This makes it a practical choice when replacing a failed upstream oxygen sensor on a Buick Allure or Audi A8 Quattro, or when servicing the listed BMW and Volkswagen models with the correct bank and side orientation.

What This Sensor Helps Address

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

Installation Notes and Tips

Confirm the exact year, make, model, bank, and position before ordering. This part is listed for upstream, upstream right, and upstream left locations depending on the vehicle application. Inspect the sensor wiring harness and connector for damage during replacement, since physical wear can shorten sensor life and affect operation. The threaded mounting design should be matched to the original sensor location for proper installation.

For fitment-based searches, this part is commonly selected for upstream oxygen sensor replacement on 2005-2008 Buick LaCrosse, 2004-2006 BMW X5, and 2007 Audi A8 Quattro applications. It also serves listed upstream positions for Buick Allure and Volkswagen Touareg models.

Quality Assurance

Walker Products has produced engine management and fuel system components since 1946 and operates as an ISO 9001/TS 16949 certified company. The 350-35041 reflects that application-specific approach, with fitment and connector design matched to the listed vehicles for reliable replacement service.