Walker 350-34132 Oxygen Sensor - Downstream

Walker 350-34132 Oxygen Sensor for Mazda Protege

Walker Products 350-34132 is a heated downstream oxygen sensor built as a specific-fit OE replacement for select Mazda Protege applications. It is engineered to deliver the ECU feedback needed for proper fuel control and emissions monitoring on the listed vehicles.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for direct replacement use. For Mazda Protege owners, this downstream sensor is matched to the application, mounting position, connector style, and wiring requirements called out in the fitment data.

Key Features

• Specific-fit heated oxygen sensor for downstream placement
• Fits select 1999-2003 Mazda Protege applications
• Threaded mounting type with 18.0 mm thread diameter
• 4-wire design with 20-gauge wiring
• Radiused polygon female connector
• Wiring harness length: 32.2
• Overall length: 35.75

Detailed Description

The Walker 350-34132 oxygen sensor is designed for downstream use on compatible Mazda Protege models, including B1S2 and bank 1 sensor 2 applications listed in the fitment data. As a heated sensor, it helps the ECU monitor exhaust oxygen content after the catalyst, supporting accurate diagnostic feedback and emissions system operation. This part number, 350-34132, is built for specific vehicle placement rather than universal use, which helps ensure the connector, harness length, and threaded mount align with the original application.

Fits 2002-2003 Mazda Protege, downstream. Fits 2001 Mazda Protege, downstream. Fits 1999-2000 Mazda Protege, downstream. This part cross-references no listed alternate part numbers in the provided data.

What It Helps Address

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

Installation Notes and Tips

Confirm the vehicle is a Mazda Protege with the exact downstream position shown in the fitment data before ordering. Match the connector shape, wire count, and threaded mounting style to the original sensor. Inspect the sensor wiring harness and connector for heat damage, corrosion, or physical wear before installation, since damaged wiring can shorten sensor life and affect readings.

Quality Assurance

Walker Products has produced engine management components since 1946 and manufactures sensors for OE-style replacement applications worldwide. The brand is ISO 9001/TS 16949 certified, with product development focused on application-specific fitment and ECU feedback requirements.