Walker 350-34272 Oxygen Sensor - Downstream

Walker 350-34272 Oxygen Sensor for BMW

Walker Products 350-34272 is a specific-fit heated oxygen sensor engineered as an OE-style replacement for select BMW applications. It is built for downstream use and provides the ECU with the feedback needed to monitor exhaust performance and emissions control.

Compatible with BMW Z4 and BMW M3 downstream applications, this sensor is a direct-fit option for drivers addressing fault codes, poor fuel economy, or an illuminated malfunction indicator light.

Key Features

• Part number: 350-34272
• Heated oxygen sensor design for faster operating response
• Specific-fit application for correct sensor placement
• 4-wire configuration with male connector
• Threaded mounting type with 18.0 mm thread diameter
• Wiring harness length: 41.65
• Overall length: 45.2
• Connector shape: radiused polygon
• Fits downstream oxygen sensor locations

Detailed Description

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors built for OE replacement use across a wide range of vehicles. The 350-34272 is manufactured for the specified application and fitment position, helping restore the diagnostic feedback the ECU expects from the downstream sensor circuit. For BMW Z4 and BMW M3 models, this sensor supports emissions monitoring on cylinders 1-3 downstream applications.

Walker Products has supplied engine management and fuel system components since 1946 and operates with Automotive ISO9001/TS 16949 certification. The 350-34272 reflects that application-specific approach, with the correct connector style, wire count, and threaded mounting configuration for the listed vehicles.

What It Helps Address

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

Installation Notes and Tips

Before replacement, inspect the sensor wiring harness and connector for heat damage, abrasion, or corrosion. Confirm the downstream mounting location and verify thread size and connector shape match the original part. If the vehicle has stored fault codes, clear them after installation and confirm the repair with a scan tool.

Fits 2006-2008 BMW Z4, downstream. Fits 2001-2006 BMW M3, downstream. Fits 2001-2002 BMW Z3, downstream.

Quality Assurance

Walker Products manufactures this oxygen sensor as an OE-style replacement under its Walker Products Aftermarket line, with application-specific fitment and ECU feedback requirements in mind. Part number 350-34272 is built for the listed BMW downstream applications.