Walker 350-34330 Oxygen Sensor - Downstream

Walker 350-34330 Oxygen Sensor for BMW Downstream Applications

Walker Products 350-34330 is a heated oxygen sensor built for specific downstream BMW applications. It is engineered as an OE-style replacement to restore accurate exhaust feedback to the ECU, helping maintain proper fuel control and emissions performance.

Key Features

• Heated oxygen sensor for downstream placement
• Specific fit design for targeted BMW applications
• 4-wire configuration with 22-gauge wiring
• Threaded mounting with 18.0 mm thread diameter
• Radiused polygon male connector for application-specific connection
• Wiring harness length: 27.09 in.; overall length: 30.63 in.

Product Details

Walker Products Aftermarket focuses on engine management and oxygen/air-fuel sensors developed as OE replacement parts for a wide range of vehicles. Part number 350-34330 is built for downstream use and provides the diagnostic feedback the ECU expects from the sensor location. For BMW models such as the X3, X5, X6, 535i, 640i, and 740i, this sensor supports accurate exhaust monitoring on the specified bank and sensor positions listed in the fitment data. This part cross-references Walker Products Aftermarket applications for the same vehicle coverage.

What This Sensor Helps Address

• Check engine light related to downstream oxygen sensor faults
• Poor fuel economy caused by incorrect exhaust feedback
• Rough engine operation tied to sensor signal issues
• Elevated exhaust emissions from inaccurate air-fuel monitoring
• Fault codes stored in the ECU for affected sensor circuits

Installation Notes and Fitment

Compatible With specific BMW downstream applications only. Confirm the bank and sensor position before ordering, especially on models where the fitment notes specify Bank 1 Sensor 2 or Bank 2 Sensor 2. Fits 2010-2018 BMW X3, downstream; 2011-2013 BMW X5, downstream; 2011-2016 BMW X6, downstream; 2011-2016 BMW 535i, downstream; 2012-2017 BMW 640i, downstream; 2013-2015 BMW 740i, downstream; and additional listed BMW applications in the fitment table. Inspect the sensor, wiring harness, and connector for damage before installation, since physical wear can shorten service life.

Quality Assurance

Walker Products has produced engine management and fuel system components since 1946 and operates as an ISO 9001 / TS 16949 certified company. The 350-34330 oxygen sensor is manufactured for specific application fitment and ECU feedback requirements.