Walker 350-35057 Oxygen Sensor - Upstream

Walker 350-35057 Oxygen Sensor Overview

Walker Products 350-35057 is a heated upstream oxygen sensor built as a specific-fit OE-style replacement for select Hyundai and Kia applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper air-fuel control and emissions monitoring.

Compatible with 2004-2009 Kia Spectra, 2005-2009 Kia Spectra5, and 2004-2009 Hyundai Elantra upstream applications, this sensor is a direct-fit option for Bank 1 Sensor 1 service needs. The Walker Products Aftermarket line focuses on application-specific engine management and oxygen sensor coverage for import vehicles.

Key Features

• Part number: 350-35057
• Heated oxygen sensor for upstream placement
• Specific fitment for targeted vehicle applications
• 5-wire design with 20-gauge wiring
• Threaded mounting type with 18.0 mm thread diameter
• Radiused polygon male connector
• Wiring harness length: 19.21
• Overall length: 22.76

Detailed Description

Walker Products 350-35057 is designed for upstream oxygen sensor replacement where precise ECU feedback is required. As a heated sensor, it helps the engine management system monitor exhaust oxygen content more quickly after startup, supporting accurate fuel control and emissions diagnostics. The specific-fit design, connector shape, and threaded mounting configuration are intended to match the listed applications without modification.

This part is a strong match for long-tail searches such as upstream oxygen sensor for 2004-2009 Kia Spectra, Bank 1 Sensor 1 oxygen sensor for 2005-2009 Kia Spectra5, and 2004-2008 Hyundai Elantra front oxygen sensor replacement. The Walker 350-35057 also aligns with 2009 Hyundai Elantra upstream service requirements noted for B1S1 applications.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Poor fuel economy caused by incorrect air-fuel feedback
• Rough engine operation from inaccurate exhaust sensing
• Elevated exhaust emissions from a failing upstream sensor
• Fault codes stored in the ECU for sensor-related issues

Installation Notes

Confirm the vehicle’s year, make, model, and upstream position before ordering. For 2009 Hyundai Elantra, verify the build date and B1S1 application details listed in the fitment notes. Inspect the sensor wiring harness and connector for damage during replacement, since physical wear can shorten sensor life and affect operation.

Because this is a threaded, specific-fit oxygen sensor, proper thread engagement and connector alignment are important during installation. Always compare the original sensor configuration to the replacement part number 350-35057 before service.

Quality Assurance

Walker Products has produced engine management and oxygen sensor components since 1946 and operates as an Automotive ISO9001/TS 16949 certified company. The Walker Products Aftermarket line is developed around application-specific fitment and ECU feedback requirements for listed vehicles.