The effects of low temperatures on emissions from gasoline passenger vehicles were investigated. The measured substances are particulate matter (PM), number of solid particulate matter (PN), greenhouse gas (GHG) components (carbon dioxide (CO2), nitrous oxide, and methane). PM and PN emissions were affected differently by low temperature depending on the fuel injection control of the test vehicles. Emissions from the vehicle with port fuel injection engine increased as the ambient temperature decreased. The effect of low temperatures on other vehicles with gasoline direct injection engine was not confirmed under hot start conditions, and emissions tended to increase as the temperature decreased under hot start conditions. GHG emissions increased at lower temperatures regardless of starting conditions, confirming the effect of low temperatures on emissions. The low temperature effect on GHG emissions reflects the low temperature effect on CO2 emissions, which account for 99% of GHG.
View full abstract