Walker 350-34640 Oxygen Sensor - Downstream or Upstream

Walker 350-34640 Oxygen Sensor for Mini Cooper

Walker Products 350-34640 is a heated oxygen sensor built as a specific-fit OE replacement for select Mini Cooper applications. It is engineered to provide the ECU with the feedback needed for accurate fuel control and emissions monitoring.

For Mini Cooper owners searching for an upstream oxygen sensor or a downstream bank 1 sensor 2 replacement, this Walker Products Aftermarket part is built around the application, connector style, and mounting position required for the vehicle.

Key Features

• Heated oxygen sensor for faster operating response
• Specific-fit design for the listed Mini Cooper applications
• 4-wire configuration with 20-gauge wiring
• Female connector with radiused polygon shape
• Threaded mounting type with 18.0 mm thread diameter
• Wiring harness length: 22.17 in.; overall length: 25.71 in.

Product Details

Walker Products Aftermarket 350-34640 is part of the Walker Products Engine Management line, which focuses on replacement sensors and fuel system components for OE-style service needs. This oxygen sensor is manufactured for the specified fitment position so it can deliver the diagnostic feedback expected by the ECU on covered Mini Cooper models. It is listed for 2002-2008 Mini Cooper upstream and downstream positions, and for 2009 Mini Cooper upstream service.

Fits 2009 Mini Cooper, upstream. Fits 2002-2008 Mini Cooper, upstream. Fits 2002-2008 Mini Cooper, downstream. This part cross-references Monroe Shocks & Struts (e.g., 172286, 182286) for the same application.

What It Helps Address

• Check engine light related to oxygen sensor performance
• Poor fuel economy caused by incorrect air-fuel feedback
• Rough engine operation from inaccurate exhaust readings
• Elevated exhaust emissions from a failing sensor
• Fault codes stored in the ECU for sensor-related issues

Installation Notes

Before replacement, inspect the sensor wiring harness and connector for heat damage, corrosion, or physical wear. Confirm the mounting position, thread size, and connector style match the vehicle before installation. For Mini Cooper upstream and downstream service, verify the exact sensor location called out by the diagnostic code and vehicle application.

Quality Assurance

Walker Products states that its engine management sensors are developed as OE replacement parts and manufactured under ISO 9001/TS 16949 quality systems. The brand has supplied engine management and fuel system components since 1946.