You are here:
CHARACTERIZATION OF EMISSIONS FROM MALFUNCTIONING VEHICLES FUELED WITH OXYGENATED GASOLINE-ETHANOL (E-10) FUEL-PART II
Citation:
Stump, F D., S B. Tejada, D L. Dropkin, C. Loomis, AND C. Pack. CHARACTERIZATION OF EMISSIONS FROM MALFUNCTIONING VEHICLES FUELED WITH OXYGENATED GASOLINE-ETHANOL (E-10) FUEL-PART II. U.S. Environmental Protection Agency, Washington, D.C., EPA/600/R-01/053 (NTIS PB2002-107676), 2001.
Description:
A 1993 Ford Taurus and a 1995 Chevrolet Achieva were tested using three different fuels: (1) a winter grade (E-10) fuel containing 10% (vol.) 200 proof ethanol, (2) a winter grade (WG) fuel without any oxygen containing compounds, and (3) a summer grade (SG) fuel without oxygenates. Vehicle emissions were characterized at test temperatures of 75 ( SG fuel only), 20, 0, and -20 degreeF. The vehicles were tested under a mode in which the vehicles were tuned to manufacturers specifications (NM mode) and under two simulated malfunction modes: 1) the oxygen (O2 mode) sensor was disconnected and 2) the exhaust gas recirculating valve (EGR mode) was disconnected and plugged. The malfunction modes were not tested simultaneously. The vehicles were tested on the Urban Dynamometer Driving Schedule (UDDS) of the Federal Test Procedure (FTP). Four IM240 test cycles were run after each of the UDDS tests and the exhaust particulate matter (PM2.5 and PM10), from the four IM240 driving cycles were collected on single filters. The gaseous emissions were collected and analyzed for total hydrocarbons, carbon monoxide, oxides of nitrogen, speciated (individual) hydrocarbons, speciated (individual) aldehydes, ethanol, methanol, 2-propanol, methyltertiarybutyl (MTBE) ether, and ethyltertiarybutyl (ETBE) ether.
Hydrocarbon emissions generally increased as test temperature decreased for both vehicles, fuels, and test modes. The E-10 fuel reduced some emissions and increased others, while disconnecting the O2 sensor increased emissions over the other two modes. The trend for carbon monoxide and oxides of nitrogen emissions showed a general increase in emission rates as the testing temperature decreased. When the O2 sensor was disabled, the trend showed increasing carbon monoxide emissions and when the EGR valve was disabled it was observed that the oxides of nitrogen emissions generally increased.
The emissions of the toxic compounds benzene and 1,3-butadiene tended to increase as the testing temperature decreased. Disconnecting the O2 sensor generally increased the emissions of these toxic compounds when compared with the NM mode emissions. The E-10 fuel generally reduced both benzene and 1,3-butadiene emissions from both vehicles. The measured emissions of formaldehyde and acetaldehyde from the test vehicles show a general increase in emissions as test temperature decreased with both the base and E-10 fuels.
The PM2.5 and PM10 particulate emission rates were comparable. The particulate emissions from both vehicles followed the HC emission trend and increased as the test temperature decreased. The E-10 fuel reduced particulate emissions from the Taurus at all test conditions with the exception of when testing at 20 degreeF in the EGR mode but the effect of the E-10 fuel on Achieva PM2.5 were not well defined. The Taurus emitted more particulate matter than the Achieva at all test conditions except when tested in the NM mode with SG fuel. Both vehicles emitted more particulate matter when the O2 sensor was disconnected.
The information in this document has been funded wholly by the United States Environmental Protection Agency under Contract 68-D5-0156 to Clean Air Vehicle Technology Center, Inc. It has been subjected to the Agency's peer and administrative review and has been approved for publication as an EPA document. Mention of trade names or commercial products does not constitute an endorsement or recommendation for use.