The 5-wire wide-band oxygen sensor is a replacement sensor for select 2011-2024 BMW and Mini applications in the upstream position. It measures the exhaust air-fuel ratio across a broad range so the engine computer can meter fuel precisely. A built-in heater brings the element to operating temperature quickly after a cold start.

Walker Products 350-35091 Oxygen Sensor Features:

• Fits 2011-2013 BMW 135i, 335i, 335i xDrive; 2011-2012 BMW 535i xDrive; 2011-2017 BMW X3; 2012-2013 BMW 640i; 2013 BMW 135is, ActiveHybrid 3, M135i
• Fits 2013-2014 BMW 640i Gran Coupe, 740Li, 740i; 2013-2020 BMW X1; 2014-2016 BMW 335i GT xDrive; 2014 BMW 640i xDrive Gran Coupe; 2015 BMW X4; 2016-2018 BMW 220i
• Also fits select BMW and Mini applications
• Sensor location by application: B1S1 (bank and sensor number)
• 5-wire wide-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 750 mm (29.5 in.) overall length
• Male rectangle connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue