Delphi ES20394 Oxygen Sensor Delphi oxygen sensors have contamination resistance to silicone, phosphorous and other fuel and oil additives due to a patented protective sensor coating Delphi oxygen sensors feature OE connectors and wire lengths within three inches of OE specifications; nearly three-quarters of the line is the exact OE length Delphi oxygen sensors go into closed loop with the ECM faster, reducing pollutants and improving emissions Delphi oxygen sensors are subjected to rigorous testing for durability, performance and environmental compliance Delphi's exclusive poison-protection coating protects elements from contaminants, which can trigger 'check engine lights' and premature sensor failure