The 4-wire narrow-band oxygen sensor is a replacement sensor for select 2005-2017 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 350-34509 Oxygen Sensor Features:

• Fits 2005-2008 Audi A4; 2005-2009 Audi A4 Quattro; 2006-2009 Audi A6, Seat Cordoba; 2006-2011 Audi A6 Quattro; 2006-2017 Seat Ibiza
• Fits 2010 Seat Nuevo Ibiza, Volkswagen Bora; 2011-2012 Seat Leon; 2013-2017 Volkswagen Polo
• Sensor location by application: B1S1 (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, 600 mm (23.6 in.) overall length
• Male rectangle connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue