The 4-wire narrow-band oxygen sensor is a replacement sensor for select 2005-2022 Audi, Seat and Volkswagen applications. It signals whether the exhaust is running rich or lean so the engine computer can trim fuel delivery. A built-in heater brings the element to operating temperature quickly after a cold start.

Walker Products 350-34223 Oxygen Sensor Features:

• Fits 2007-2015 Audi A6 Quattro; 2007-2012 Audi A8 Quattro; 2007-2010 Audi Q7; 2009-2016 Audi A4, A4 Quattro; 2010-2016 Audi A5
• Fits 2010-2017 Audi A5 Quattro, Volkswagen Tiguan; 2011-2015 Audi A1, Seat Freetrack; 2011-2018 Audi A3, Volkswagen Touareg; 2011-2013 Audi A3 Quattro; 2011-2017 Audi Q5
• Also fits select Audi, Seat and Volkswagen applications
• Sensor locations by application: B1S1, B1S2, B1S3, B2S2 (bank and sensor number)
• Used in the center positions, depending on application
• 4-wire narrow-band oxygen sensor
• Built-in heater for fast warm-up
• M18x1.5 threaded mounting with a 22 mm hex, 800 mm (31.5 in.) overall length
• Male rectangle connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue