Walker 350-64004 Oxygen Sensor - Upstream

Walker 350-64004 Oxygen Sensor Overview

Walker Products 350-64004 is a heated oxygen sensor built as a specific-fit OE replacement for select Subaru applications. It is engineered to provide the ECU with the exhaust feedback needed for fuel control and emissions monitoring, making it a direct choice for 2004 and 2006 Subaru Baja upstream service.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for application-specific fitment. The 350-64004 follows that approach with the correct threaded mounting, connector style, wire count, and harness length for the intended position.

Key Features

• Heated oxygen sensor for upstream exhaust monitoring
• Specific fit for the intended vehicle application
• Threaded mounting type with 18.0 mm thread diameter
• 4-wire design with 20-gauge wiring
• Radiused polygon male connector
• Wiring harness length: 35.35
• Overall length: 38.9

Detailed Description

The Walker 350-64004 oxygen sensor is designed for Subaru Baja upstream placement, including Bank 1 Sensor 1 service on the listed vehicles. For 2004 Subaru Baja and 2006 Subaru Baja models, this sensor helps the ECU monitor exhaust oxygen content so the engine management system can adjust air-fuel delivery and track emissions performance. If you are searching for a Walker 350-64004 oxygen sensor for Subaru Baja upstream replacement, this part is built around the application-specific fitment details that matter most: connector shape, wire configuration, and threaded installation.

Walker Products Aftermarket has supplied engine management components since 1946, and this sensor line is developed as an OE-style replacement for many vehicles worldwide. The part number 350-64004 is intended for the exact sensor position listed in the fitment data, helping maintain proper diagnostic feedback to the ECU.

Vehicle Fitment

• Fits 2004 Subaru Baja, Upstream
• Fits 2006 Subaru Baja, Upstream

What It Helps Address

• Check engine light related to upstream oxygen sensor faults
• Poor engine performance caused by inaccurate exhaust feedback
• Increased fuel consumption from incorrect air-fuel control
• Higher exhaust emissions from a failing sensor
• Stored ECU fault codes tied to Bank 1 Sensor 1 operation

Installation Notes

Confirm the vehicle uses the upstream sensor position shown in the fitment data before ordering. Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion, since physical damage can shorten sensor life and affect signal quality. Verify thread size, connector shape, and wire count against the original part before installation.

Quality Assurance

Walker Products manufactures engine management sensors under ISO 9001/TS 16949 quality systems. The 350-64004 is built for the specified application and position to deliver the diagnostic feedback expected by the ECU.