Walker 250-25162 Oxygen Sensor - Upstream

Walker OE Base Oxygen Sensor for BMW

Walker OE Base Sensor 250-25162 is a specific-fit wide-band oxygen sensor built for upstream engine management feedback on select BMW applications. It is engineered to match the original sensor location and signal requirements for the ECU, helping maintain accurate air-fuel control on vehicles such as the BMW 320i, 328i, X3, and X5.

Key Features

• Wide-band oxygen sensor for precise upstream exhaust monitoring
• Heated design for faster operating temperature and stable signal output
• Specific-fit application for direct placement on the vehicle
• 5-wire, 5-terminal configuration with rectangular female connector
• Spade terminal type with male terminal gender
• M18 x 1.5 thread size and 22 mm wrench size
• OE Base Sensor line focused on original-equipment-style replacement fitment

Product Details

Walker Products developed the OE Base Sensor line as an original-equipment replacement solution for engine management and oxygen/air-fuel sensor applications. Part number 250-25162 is designed for upstream B1S1 placement and is listed for a broad range of BMW models from 2012 through 2018, including the BMW 228i, 320i, 328i, 428i, 528i, X1, X3, X4, X5, and Z4. This sensor is intended to provide the diagnostic feedback the ECU expects from the original sensor location, supporting accurate fuel control and emissions monitoring.

This part cross-references Bosch 17098 and Denso 234-9005 for the same application.

What This Sensor Helps Address

• Check engine light related to upstream oxygen sensor performance
• Poor fuel economy caused by incorrect air-fuel readings
• Rough running or drivability issues tied to sensor feedback loss
• Elevated exhaust emissions from inaccurate mixture control
• Fault codes stored in the ECU for the affected sensor circuit

Installation Notes and Tips

Verify the connector shape, terminal count, thread size, and upstream B1S1 position before installation. Inspect the sensor wiring harness and connector for heat damage, corrosion, or broken terminals, since physical damage can shorten sensor life and affect signal quality. Confirm the vehicle application against the listed BMW fitment for 2012-2018 models before replacing the original sensor.

Quality Assurance

Walker Products has manufactured engine management components since 1946 and operates as an ISO 9001/TS 16949 certified company. The OE Base Sensor line is built around application-specific fitment and ECU feedback requirements for dependable replacement use.