Walker 350-34825 Oxygen Sensor - Downstream

Walker 350-34825 Oxygen Sensor for Subaru

Walker Products 350-34825 is a heated oxygen sensor built as a specific-fit OE replacement for select Subaru applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper fuel control and emissions performance on downstream Subaru systems.

Key Features

• Heated oxygen sensor for downstream exhaust monitoring
• Specific-fit design for direct application matching
• 4-wire configuration with a female radiused polygon connector
• Threaded mounting with 18.0 mm thread diameter
• Wiring harness length: 6.49 in.; overall length: 9.84 in.
• Wire gauge: 20

Product Details

Walker Products Aftermarket 350-34825 is part of the Walker Products Engine Management and Oxygen/Air-Fuel sensor line, developed as an OE-style replacement for vehicles worldwide. This heated downstream oxygen sensor is built for specific fitment and application-based feedback, making it a direct replacement choice for Subaru models that use a threaded, 4-wire sensor in the downstream position. It is listed for 2021-2024 Subaru Ascent, Legacy, and Outback, plus 2021 Subaru WRX, with additional downstream coverage for 2014-2018 Subaru Forester and select 2015-2020 Subaru WRX applications. This part number, 350-34825, is intended for vehicles that require downstream bank 1 sensor 2 coverage on specific models.

Walker Products has produced engine management components since 1946 and operates with Automotive ISO9001/TS 16949 certification. The Walker Products Aftermarket line focuses on application-specific sensor fitment and ECU feedback requirements for modern emissions systems.

What It Helps Address

• Check engine light related to downstream oxygen sensor faults
• Poor fuel economy caused by inaccurate exhaust feedback
• Elevated exhaust emissions from a failing sensor
• Rough engine operation tied to incorrect air-fuel correction
• Fault codes stored in the ECU for the affected sensor circuit

Installation Notes

Verify the connector shape, wire count, thread diameter, and downstream position before installation. Inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion, since physical damage can shorten service life. Confirm the vehicle’s exact Subaru application and sensor location before ordering; 350-34825 is a specific-fit part and should be matched to the required downstream configuration.

Quality Assurance

Walker Products manufactures this sensor under ISO9001/TS 16949 quality systems and designs its engine management sensors as OE replacement components for application-specific fitment and ECU feedback.