Evaluation of the Effectiveness of On-Board Diagnostic (OBD) Systems in Identifying Fuel Vapor Losses from Light-Duty Vehicles.

摘要

This document is Eastern Research Group’s (ERG’s) final report on evaluating the effectiveness of Second Generation On-Board Diagnostic (OBD) systems through a comparative analysis of evaporative emissions field data collected in the Denver area during the past four years. These field studies were performed through Cooperative Research and Development Agreements (CRADAs 471-08 and 471-A-11) between the Assessment and Standards Division (ASD) within the Office of Transportation and Air Quality (OTAQ) of the United States Environmental Protection Agency (EPA) and the Colorado Department of Public Health and Environment (CDPHE), with support provided by ERG under Work Assignments 1-2, 2-2, 2-4, 3-4 and 4-4 of Contract EP-C-06-080 with the EPA. A wealth of data has been collected at the Denver Lipan and Ken Caryl Inspection and Maintenance (I/M) lanes using a Portable Sealed Housing for Evaporative Determination (PSHED) and remote sensing devices. Because the studies took place at I/M lanes in Colorado, OBD information is also available for each vehicle.