Walker 350-34628 Oxygen Sensor - Downstream

Walker 350-34628 Oxygen Sensor for Hyundai and Kia

Walker Products 350-34628 is a heated oxygen sensor built as a specific-fit OE-style replacement for select Hyundai Sonata and Kia Optima applications. It is engineered to provide the ECU with the correct diagnostic feedback for downstream bank 1 sensor 2 service, helping restore proper emissions monitoring and engine management performance.

Key Features

• Heated oxygen sensor for downstream placement
• Specific fitment for select Hyundai Sonata and Kia Optima models
• 4-wire design with female connector
• 18.0 mm thread diameter and threaded mounting type
• Wiring harness length: 18.23 in.; overall length: 21.77 in.
• Radiused polygon connector shape for application-specific fitment
• Walker Products Aftermarket line engineered for OE replacement use

Product Details

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensor replacement parts for vehicle-specific applications. Part number 350-34628 is built for downstream use and is listed for select 2009-2015 Hyundai Sonata and 2011-2015 Kia Optima models, including B1S2 applications noted in the fitment data. For shoppers searching for a downstream oxygen sensor for Hyundai Sonata or a Kia Optima oxygen sensor replacement, this part number provides a direct-match option for the listed vehicles.

As an emissions sensor, this component helps the ECU monitor exhaust conditions and maintain proper fuel control strategy. When an oxygen sensor begins to fail, common symptoms can include poor engine operation, higher fuel consumption, increased exhaust emissions, or a malfunction indicator light. The sensor, wiring harness, and connector should also be inspected for physical damage during diagnosis. Walker Products 350-34628 is designed for the specific application and fitment position required by the vehicle.

What It May Help Resolve

• Check engine light related to downstream oxygen sensor faults
• Poor fuel economy caused by inaccurate exhaust feedback
• Rough running or drivability issues tied to emissions sensor failure
• Elevated exhaust emissions from a worn or damaged sensor
• Fault codes stored in the ECU for B1S2 or downstream sensor circuits

Installation Notes and Tips

Confirm the vehicle’s emissions configuration and build date before ordering, especially for 2011 Hyundai Sonata applications with California and non-California notes. This part is listed for downstream bank 1 sensor 2 service on the specified vehicles, and fitment should be matched to the exact model year and emissions package. Inspect the connector, harness, and surrounding wiring before installation, and verify the threaded mounting location is clean and undamaged.

Fits 2011-2015 Kia Optima, downstream; fits 2012-2014 Hyundai Sonata, downstream; and fits 2009-2011 Hyundai Sonata, downstream, for the listed B1S2 and emissions-specific applications.

Quality Assurance

Walker Products has produced engine management and sensor components since 1946 and operates as an ISO 9001/TS 16949 certified company. The 350-34628 is part of the Walker Products Aftermarket line, developed as a vehicle-specific replacement for the listed Hyundai and Kia applications.