Walker 350-64020 Oxygen Sensor - Upstream

Walker 350-64020 Oxygen Sensor for Subaru

Walker Products 350-64020 is a heated upstream oxygen sensor built as an OE-style replacement for specific Subaru applications. It is engineered for direct fitment and ECU feedback on vehicles that rely on accurate air-fuel monitoring to maintain drivability and emissions performance.

Key Features

• Heated oxygen sensor for upstream placement
• Specific-fit design for selected Subaru Impreza, WRX, Forester, Legacy, and Outback applications
• 4-wire configuration with 20-gauge wiring
• Radiused polygon male connector for application-specific connection
• Threaded mounting with 18.0 mm thread diameter
• Overall length: 11.93 in.; wiring harness length: 8.39 in.

Product Details

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors engineered to match original equipment requirements. Part number 350-64020 is a specific-fit upstream oxygen sensor that provides the diagnostic feedback the ECU expects on supported Subaru models, including 2009-2014 Subaru Impreza, 2012-2014 Subaru WRX, 2011-2013 Subaru Forester, and 2008-2009 Subaru Legacy and Outback. This part number is also referenced as Walker 350-64020 for catalog and search use.

The Walker Products line is built around application-specific sensor fitment, connector style, and mounting configuration so the replacement matches the vehicle’s original sensor location and signal requirements. This part cross-references no additional part numbers listed for the same application.

What It Helps Address

• Check engine light related to upstream oxygen sensor faults
• Poor engine performance caused by incorrect air-fuel feedback
• Increased fuel consumption from inaccurate sensor readings
• Higher exhaust emissions from a failing oxygen sensor
• Fault codes stored in the ECU for sensor or related system issues

Installation Notes

Confirm the vehicle’s upstream position before installation. Inspect the sensor wiring harness and connector for damage, since physical wear can shorten sensor life and affect signal quality. Verify thread size, connector shape, and harness length against the original part before replacement. Fits 2009-2014 Subaru Impreza, Upstream; Fits 2012-2014 Subaru WRX, Upstream; Fits 2011-2013 Subaru Forester, Upstream; Fits 2008-2009 Subaru Legacy, Upstream; Fits 2008-2009 Subaru Outback, Upstream.

Quality Assurance

Walker Products is an automotive ISO 9001/TS 16949 certified company with a long history in engine management and fuel system components. The 350-64020 oxygen sensor is manufactured for specific application fitment and ECU feedback requirements.