Walker 350-34277 Oxygen Sensor

Walker 350-34277 Oxygen Sensor Overview

Walker Products 350-34277 is a heated oxygen sensor built as an OE-style replacement for specific Toyota and Lexus applications. It is engineered for the correct fitment position and ECU feedback, helping maintain accurate air-fuel monitoring on vehicles such as the Toyota 4Runner, Lexus GX460, and Land Cruiser.

Walker Products Aftermarket focuses on engine management and oxygen sensor coverage for late-model and older import vehicles. The 350-34277 follows that approach with application-specific fitment, a threaded mount, and a 4-wire heated design for direct replacement use.

Key Features

• Part number: 350-34277
• Heated oxygen sensor for precise exhaust feedback
• Specific-fit design for confirmed Toyota and Lexus applications
• 4-wire configuration with 20-gauge wiring
• Radiused polygon male connector for vehicle-specific connection
• Threaded mounting with 18.0 mm thread diameter
• Overall length: 11.93 in.; wiring harness length: 8.39 in.

Detailed Description

This Walker oxygen sensor is manufactured for the exact application and position listed in the fitment data, including downstream right and upstream left or right locations depending on the vehicle. It is intended to provide the diagnostic feedback the ECU expects, which is important for maintaining proper fuel control and emissions system operation. The 350-34277 is a direct-fit replacement for many Toyota and Lexus models, including 4Runner, GX460, LX570, Land Cruiser, Yaris, and several older Lexus platforms.

Walker Products has supplied engine management and oxygen/air-fuel sensors since 1946 and builds this aftermarket line around OE replacement requirements. If the original sensor has triggered a fault code, caused rough running, increased fuel use, or illuminated the MIL, this replacement addresses the sensor position specified by the vehicle application.

This part cross-references Walker Products Aftermarket 350-34277 for the same application.

Common Issues This Sensor Can Address

• Check engine light related to oxygen sensor performance
• Poor fuel economy from inaccurate exhaust feedback
• Rough engine operation caused by a failing heated O2 sensor
• Elevated exhaust emissions from incorrect air-fuel correction
• Stored ECU fault codes tied to the affected sensor circuit

Installation Notes and Tips

• Verify the exact position before ordering: upstream left, upstream right, downstream, or downstream right.
• Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion before installation.
• Confirm thread diameter and connector style match the original sensor.
• Use the vehicle’s service information for torque and routing guidance.
• Clear diagnostic trouble codes after installation and confirm normal sensor operation.

Quality Assurance

Walker Products manufactures this sensor as an OE replacement part for specific vehicle applications and positions. The brand states its engine management and oxygen sensor products are developed under Automotive ISO9001/TS 16949-certified processes.