Evaluation of Emissions from Light Duty Trucks with and without the Use of a Gasoline Particulate Filter

The goal of this study was to investigate the emission impacts of replacing the OEM three-way catalyst on light duty trucks using various, commercially available, gasoline particulate filter (GPF) configurations. Three light duty trucks were tested: a Port Fuel Injection (PFI) PFI_1 and two Gasoline Direct Injection (GDI) vehicles GDI_1 and GDI_2. The testing of these vehicles was conducted on a chassis dynamometer in a controlled test cell environment at two temperatures (25 °C and -7 °C) using the Federal Test Procedure (FTP-75) and the US06 test procedure. All three vehicles were tested in stock OEM configuration followed by testing PFI_1 and GDI_1 with a non-catalyzed GPF and GDI_2 with a catalyzed GPF. GDI_2 was also tested on-road using a portable emissions measurement system (PEMS) with and without the use of the catalyzed GPF. Gaseous emissions, Particulate Matter (PM), Black Carbon (BC) and Particle Number (PN) emissions were measured. Results for the non-catalyzed GPF configuration on PFI_1 and GDI_1 showed a decrease in PM at both standard and cold temperatures, with the biggest decrease being 89% for GDI_1 during the FTP-75 at 25 °C. An increase in NOx was also observed for both vehicles at both standard and cold temperature testing with the non-catalyzed GPF installed. GDI_2 catalyzed GPF results showed a decrease in both PM and NOx at both standard and cold temperature testing with the biggest decrease in PM being 87% during the FTP-75 at -7 °C. On-road results for GDI_2 showed a 67% decrease in PN with no significant difference in NOx while equipped with a catalyzed GPF.