CRC 05063 Emissions Test Formula contains powerful detergent additives strong enough to remove harmful carbon and varnish deposits. It cleans the fuel system and emission control components in gas-powered vehicles. Use the guaranteed-to-pass-emissions test formula every 3 000 miles to improve fuel economy acceleration and reduce emissions. It reduces CO HC and Nitrogen Oxide emissions and is effective for both tailpipe exhaust analysis and OBD II on-board diagnostics emissions testing methods.