O2 Oxygen Sensor for Audi A4/A6 Porsche Cayenne VW Passat Touareg (2000-2006)Turn off that glowing Check Engine Light and restore the fuel efficiency of your German machine without the nightmare of splicing universal wires. Direct Fit Oxygen Sensor Set (4 Pack) for Audi, VW & Porsche (1470mm Wire Length) If you own an Audi, VW, or Porsche from the early 2000swhether it's the B5 B6 Passat, the MK4 Beetle, or the powerhouse Cayenneyou are likely familiar with the dreaded Check Engine Light (CEL). Often triggered by codes like