Walker 350-34293 Oxygen Sensor - Upstream

Walker 350-34293 Oxygen Sensor for Montero

Walker Products 350-34293 is a heated oxygen sensor built as a specific-fit OE replacement for select Mitsubishi applications. It is engineered for the upstream position on 1990-1991 Mitsubishi Montero models and is designed to provide the ECU with the feedback needed for proper fuel control and emissions monitoring.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for application-specific fitment. The 350-34293 follows that approach with a threaded, 4-wire heated design, a female radiused-polygon connector, and a 46.38-inch wiring harness for the listed vehicle application.

Key Features

• Specific-fit oxygen sensor for the upstream location
• Heated sensor design for faster operating response
• 4-wire configuration with 22-gauge wiring
• Female radiused-polygon connector
• Threaded mounting with 18.0 mm thread diameter
• Overall length: 49.92 inches
• Wiring harness length: 46.38 inches

Detailed Description

This Walker oxygen sensor is made for 1990-1991 Mitsubishi Montero upstream applications and is intended to replace the original sensor with the correct fitment position and ECU feedback characteristics. As an emissions control sensor, it helps the engine management system monitor exhaust oxygen content so the vehicle can maintain proper air-fuel control. The Walker 350-34293 is a practical choice when servicing a Mitsubishi Montero with a failed upstream sensor or when diagnosing drivability and emissions concerns tied to sensor performance.

This part number, 350-34293, is part of Walker Products Aftermarket engine management coverage and is built for the listed application rather than universal use. If you are searching for a Mitsubishi Montero upstream oxygen sensor, Walker 350-34293 is the direct fitment reference for the confirmed model years.

What It Helps Address

• Check engine light related to upstream oxygen sensor faults
• Poor fuel economy caused by inaccurate exhaust feedback
• Rough running or inconsistent air-fuel control
• Increased exhaust emissions from a failing sensor
• Stored ECU fault codes tied to the oxygen sensor circuit

Installation Notes and Tips

Fits 1990-1991 Mitsubishi Montero, upstream. Confirm the connector shape, wire count, thread diameter, and harness length against the original sensor before installation. Inspect the sensor wiring harness and connector for heat damage, corrosion, or physical wear, since those conditions can shorten sensor life and affect diagnostic results. The threaded mounting style should be matched to the vehicle’s exhaust bung before replacement.

Quality Assurance

Walker Products states that its engine management sensors are developed as OE replacement parts for global vehicle applications and manufactured under Automotive ISO9001/TS 16949 quality systems. Part number 350-34293 reflects that application-specific approach for Mitsubishi Montero service work.