Viewer Question: Oxygen Sensors

This week John Hutchinson from Red Rocket Auto Tech is showing Paul how to Love Your Car's oxygen sensors.

Viewer Question: I failed smog. I was told that I need a new oxygen sensor and a catalytic converter. Supposedly the oxygen sensor caused damage to the catalytic converter. Why would a sensor issue damage a catalytic converter? --  Scott

Oxygen Sensors

  • Essential to making automotive emission control possible
  • Measures & compares oxygen levels in exhaust vs. outside air
  • Engine adjustments are made based on oxygen sensor output

Catalytic Converters

  • Converts toxic pollutants into less toxic pollutants
  • Unburnt fuel is removed in exhaust
  • Chemical reactions occur using internal precious metals

Open Loop Mode

  • Normal mode when engine is cold
  • Wastes fuel
  • Increases emissions
  • Causes excessive heat/stress on the catalytic converter