Walker 350-34688 Oxygen Sensor - Downstream or Upstream

Walker 350-34688 Oxygen Sensor Overview

Walker Products 350-34688 is a heated oxygen sensor built as a specific-fit OE replacement for select Mazda Protege, Mazda Protege5, and Suzuki Forenza applications. It is engineered to deliver the diagnostic feedback the ECU expects, helping maintain proper fuel control and emissions performance.

Key Features

• Heated oxygen sensor for faster operating response
• Specific-fit design for the listed vehicle applications
• 4-wire configuration with a female connector
• Threaded mounting type with 18.0 mm thread diameter
• Wiring harness length: 7.4 in.; overall length: 10.94 in.
• Radiused polygon connector shape for application-specific fitment
• Walker Products Aftermarket line for engine management and oxygen sensor replacement

Vehicle Fitment

• Fits 2004-2005 Suzuki Forenza, downstream bank 1 sensor 2.
• Fits 2001-2003 Mazda Protege, upstream bank 1 sensor 1.
• Fits 2001-2003 Mazda Protege, front oxygen sensor.
• Fits 2002-2003 Mazda Protege5, upstream bank 1 sensor 1.
• Fits 2002-2003 Mazda Protege5, front oxygen sensor.

Detailed Description

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensor replacement parts for OE-style fitment and ECU feedback. Part number 350-34688 is built for the specified mounting position and wiring layout, making it a direct-match solution for select Mazda Protege and Protege5 upstream applications as well as the downstream Suzuki Forenza location. If the original sensor has aged or the connector or harness has been damaged, this Walker 350-34688 oxygen sensor helps restore accurate exhaust monitoring for the engine control system.

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

What It Helps Address

• Check engine light related to oxygen sensor performance
• Rough running caused by incorrect air-fuel feedback
• Increased fuel consumption from inaccurate exhaust readings
• Higher exhaust emissions from a failing sensor
• Fault codes stored in the ECU for the affected sensor circuit

Installation Notes and Tips

Confirm the vehicle year, make, model, and sensor position before ordering. For these applications, verify whether the vehicle needs an upstream bank 1 sensor 1 or downstream bank 1 sensor 2 replacement. Inspect the sensor wiring harness and connector for heat damage, corrosion, or broken terminals before installation, since physical damage can shorten sensor life and affect ECU feedback.

Quality Assurance

Walker Products states that its engine management sensors are developed as OE replacement parts and manufactured under Automotive ISO9001/TS 16949 quality systems. The brand has supplied engine management and fuel system components since 1946.