This 5-wire wide-band oxygen sensor fits select 2002-2008 Audi, BMW, Buick and Volkswagen applications in the upstream position and 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 350-35041 Oxygen Sensor Features:

• Fits 2002-2004 Audi S3; 2003 Audi Allroad Quattro; 2005-2007 Audi A8 Quattro; 2002-2003 BMW 745Li, 745i; 2004-2005 BMW 545i, 645Ci; 2004-2006 BMW X5, Buick Rendezvous
• Fits 2005-2008 Buick Allure, LaCrosse; 2004-2007 Volkswagen Touareg
• Sensor locations by application: B1S1, B1S2 (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, 600 mm (23.6 in.) overall length
• Male oblong connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue