Walker 350-34407 Oxygen Sensor - Downstream or Upstream

Walker 350-34407 Oxygen Sensor for Toyota

Walker Products 350-34407 is a specific-fit heated oxygen sensor engineered as an OE-style replacement for select Toyota applications. It is built to deliver the diagnostic feedback the ECU expects, helping maintain proper fuel control and emissions performance on the vehicles listed below.

Key Features

• Heated oxygen sensor with specific fitment for the listed Toyota applications
• 4-wire design with 20-gauge wiring
• 18.43-inch wiring harness length and 21.97-inch overall length
• Male connector with radiused polygon shape
• 18.0 mm thread diameter and flange mount design
• Fits upstream and downstream positions depending on application

Product Details

Walker Products Aftermarket 350-34407 is part of the Walker Products Engine Management and Oxygen/Air-Fuel sensor line, developed for direct replacement use on specific vehicles. This oxygen sensor is intended to provide the ECU with the correct signal for air-fuel management, which is critical on Toyota 4Runner, Toyota Pickup, and Toyota Previa applications from 1991-1995. The fitment data includes upstream and downstream positions, with notes for California and non-California emissions configurations, so matching the exact vehicle build and emissions setup is important before ordering. This part cross-references Bosch 13275 for the same application.

What This Sensor Helps Address

• Check engine light related to oxygen sensor performance
• Rough running or poor drivability caused by incorrect exhaust feedback
• Increased fuel consumption from inaccurate air-fuel correction
• Higher exhaust emissions from a failing upstream or downstream sensor
• Fault codes stored in the ECU for the affected sensor circuit

Installation Notes and Fitment Tips

• Fits 1991-1995 Toyota Previa, upstream.
• Fits 1992-1995 Toyota Pickup, upstream and downstream depending on emissions package and body configuration.
• Fits 1992-1995 Toyota 4Runner, upstream.
• Confirm California emissions, Federal emissions, short bed, long bed, and dual rear wheel notes before installation.
• Inspect the sensor wiring harness and connector for damage before replacing the part.
• Verify the mounting style, thread diameter, and connector shape against the original sensor.

Quality Assurance

Walker Products has supplied engine management and fuel system components since 1946 and manufactures sensors for specific application fitment. The brand is ISO 9001/TS 16949 certified, with production focused on OE-style replacement performance and ECU feedback requirements.