Walker 350-34148 Oxygen Sensor - Downstream

Walker 350-34148 Oxygen Sensor Overview

Walker 350-34148 is a heated oxygen sensor built as a specific-fit OE replacement for select Mazda Protege and Kia Sephia applications. It is engineered to provide the ECU with the feedback needed for proper fuel control and emissions monitoring.

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors for application-specific fitment. The 350-34148 follows that approach with the correct mounting style, connector design, and wiring configuration for the listed downstream position.

Key Features

• Heated oxygen sensor for downstream bank 1 sensor 2 applications
• Specific fitment for direct vehicle application matching
• 4-wire design with 20-gauge wiring
• Threaded mounting type with 18.0 mm thread diameter
• Radiused polygon male connector for vehicle-side connection
• Wiring harness length: 11.54
• Overall length: 15.08

Detailed Description

This Walker oxygen sensor, part number 350-34148, is designed for 1995-1998 Mazda Protege and 1996-1997 Kia Sephia downstream locations. It is intended for bank 1 sensor 2 placement where the ECU relies on exhaust feedback to monitor catalyst and emissions performance. For shoppers searching for a downstream oxygen sensor for Mazda Protege or a Kia Sephia oxygen sensor replacement, this part number provides a direct-fit option with the specified connector and threaded mount.

Walker Products Aftermarket builds engine management sensors to match the application, fitment position, and diagnostic feedback requirements of the vehicle. That makes the 350-34148 a practical choice when replacing a failed downstream sensor on the listed Mazda Protege and Kia Sephia models.

What It Helps Address

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

Installation Notes

Verify the vehicle’s sensor position before ordering: this part is for downstream bank 1 sensor 2 applications only. Inspect the sensor wiring harness and connector for damage during replacement, since physical wear can shorten sensor life and affect signal quality. Confirm thread diameter, connector shape, and harness routing against the original part before installation.

Quality Assurance

Walker Products is an Automotive ISO9001/TS 16949 certified company with a long history in engine management and fuel system components. The 350-34148 is built as an OE-style replacement for the specified application and position.