Walker 350-34589 Oxygen Sensor - Downstream or Downstream Front

Walker 350-34589 Oxygen Sensor for Toyota and Lexus

Walker Products 350-34589 is a heated oxygen sensor built as a specific-fit OE replacement for select Toyota and Lexus applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper fuel control and emissions performance on vehicles such as the Toyota Supra, Toyota Highlander, and Lexus RX300.

Key Features

• Heated oxygen sensor with 4-wire design
• Specific-fit application for direct vehicle placement
• Flange mount construction
• Radiused polygon male connector
• 17.64 in. wiring harness length
• 18.0 mm thread diameter
• 21.18 in. overall length
• Walker Products Aftermarket line for engine management and oxygen/air-fuel sensors

Product Details

Walker Products 350-34589 is part of the Walker Products Aftermarket engine management sensor line, developed as an OE-style replacement for vehicles worldwide. This heated oxygen sensor is built for the specified downstream front or downstream location, depending on application, and is intended to provide the ECU with the correct signal for closed-loop fuel management. It is a direct-fit solution for select 1993-2003 Toyota Supra, 2001-2003 Toyota Highlander, and 1999-2003 Lexus RX300 applications. The part number 350-34589 is also referenced for Toyota Supra downstream oxygen sensor service needs where the factory sensor location and connector style must match the original setup.

Walker Products has supplied engine management and fuel system components since 1946 and manufactures sensors to application-specific fitment standards. This part cross-references no listed alternate part numbers in the provided data.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Rich or lean fuel mixture conditions
• Reduced fuel economy caused by inaccurate exhaust feedback
• Elevated exhaust emissions
• Poor engine operation tied to faulty downstream sensor input

Installation Notes

• Confirm the exact position before installation: downstream front or downstream, depending on vehicle.
• Inspect the sensor wiring harness and connector for heat damage, corrosion, or abrasion before replacement.
• Verify thread diameter, connector shape, and harness length match the original sensor.
• Clear stored fault codes after installation and confirm the repair with a scan tool.

Quality Assurance

Walker Products manufactures this oxygen sensor as an application-specific replacement under its automotive quality systems, including ISO 9001/TS 16949 certification referenced by the brand.