Walker 350-35025 Oxygen Sensor - Upstream

Walker 350-35025 Oxygen Sensor Overview

Walker Products 350-35025 is a heated, threaded oxygen sensor built as a specific-fit OE replacement for select Ford Escape and Audi A8 Quattro applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper air-fuel control and emissions monitoring.

Key Features

• Heated oxygen sensor for faster operating temperature and signal response
• Specific-fit design for direct application matching
• 5-wire configuration with a male radiused polygon connector
• 33.98 in. wiring harness length and 20-gauge wire
• 18.0 mm thread diameter with threaded mounting
• Overall length: 37.52 in.

Product Details

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors engineered as OE-style replacements for a wide range of vehicles. Part number 350-35025 is built for upstream placement and is listed for 2020-2021 Ford Escape, upstream, including Bank 1 Sensor 1 applications, as well as 2008-2009 Audi A8 Quattro, upstream for cylinders 4-6. If you are searching for a Walker 350-35025 oxygen sensor for a 2020-2021 Ford Escape or a 2008-2009 Audi A8 Quattro upstream location, this part is matched to the specified fitment and connector layout.

This part cross-references no additional part numbers in the provided data.

What It Helps Address

• Check engine light or malfunction indicator light related to oxygen sensor performance
• Poor engine operation caused by incorrect exhaust feedback
• Increased fuel consumption from inaccurate air-fuel ratio control
• Higher exhaust emissions from a failing upstream sensor
• Fault codes stored in the ECU tied to the affected sensor circuit

Installation Notes and Tips

Confirm the vehicle’s upstream sensor location, connector shape, wire count, and thread size before installation. Inspect the sensor wiring harness and connector for damage, since physical wear can shorten service life and affect signal quality. For best results, verify the application against the vehicle’s ECU fault code and fitment position before replacing the sensor.

Quality Assurance

Walker Products is an automotive ISO 9001 / TS 16949 certified company with a long history in engine management components. The 350-35025 is manufactured for the specified application and fitment position to provide the diagnostic feedback required by the ECU.