The oxygen sensor installs in the upstream position on 2005-2011 Audi A6 Quattro, 2007-2010 Audi A8 Quattro, 2007-2008 Audi RS4 and 2008-2015 Audi R8. 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 350-35056 Oxygen Sensor Features:

• Fits 2005-2011 Audi A6 Quattro; 2007-2010 Audi A8 Quattro; 2007-2008 Audi RS4; 2008-2015 Audi R8
• Engine coverage includes 4.2L V8, 6.0L W12 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, 1700 mm (66.9 in.) overall length
• Male oblong connector at the harness end
• Platinum electrode layer with a protective coating against combustion residue