Walker 350-34401 Oxygen Sensor - Upstream

Walker 350-34401 Oxygen Sensor Overview

Walker Products 350-34401 is an upstream oxygen sensor engineered as an OE-style replacement for specific Ford Fiesta applications. It is built to provide the ECU with the exhaust feedback needed for proper fuel control and emissions monitoring.

Compatible With 2003-2006 Ford Fiesta, upstream. This Walker Products Aftermarket oxygen sensor is listed for Bank 1 Sensor 1 service on the Ford Fiesta and is also referenced as a front oxygen sensor for the same vehicle coverage.

Key Features

• Upstream oxygen sensor for emission control system feedback
• OE-replacement design for specific vehicle fitment and sensor position
• Supports ECU monitoring for air-fuel and diagnostic response
• Walker Products Aftermarket line for engine management and oxygen sensor applications
• Part number 350-34401 for direct catalog lookup

Detailed Description

Walker Products 350-34401 is an oxygen sensor for 2003-2006 Ford Fiesta models in the upstream position. It is intended for Bank 1 Sensor 1 service, where the sensor reports exhaust oxygen content to the engine control unit so the system can adjust fueling and monitor emissions performance. The Walker Products Aftermarket line focuses on application-specific replacement parts, and this sensor follows that approach with fitment tied to the listed vehicle and position. If you are searching for a 2003 Ford Fiesta upstream oxygen sensor, 2004-2006 Ford Fiesta Bank 1 Sensor 1, or Walker 350-34401 for Ford Fiesta, this part matches the cataloged application.

This part cross-references no additional part numbers in the provided data.

What It May Help Solve

• Check engine light related to oxygen sensor performance
• Poor engine running caused by incorrect exhaust feedback
• Increased fuel consumption from inaccurate air-fuel control
• Higher exhaust emissions from a failing upstream sensor
• Stored ECU fault codes tied to the affected sensor circuit

Installation Notes and Tips

Verify the sensor location before replacement and confirm the vehicle is a 2003-2006 Ford Fiesta with upstream Bank 1 Sensor 1 coverage. Inspect the sensor wiring harness and connector for heat damage, corrosion, or broken terminals before installation. If the original sensor failed due to wiring or connector damage, correct that issue so the replacement sensor can operate properly.

Quality Assurance

Walker Products states that its engine management and oxygen/air-fuel sensors are developed as OE replacement parts and manufactured for specific applications and positions. The company is ISO 9001/TS 16949 certified and has supplied engine management and fuel system components since 1946.