Effects of Dual Port Injection and Direct-Injection Technology on Combustion Emissions from Light-Duty Gasoline Vehicles

Dual injection fuel systems combine the knock and fuel economy benefits of gasoline direct injection (GDI) technology with the lower particulate emissions of port fuel injection (PFI) systems. For many years, this technology was limited to smaller-volume, high-end, vehicle models, but these technologies are now becoming main stream. The combination of two fuel injection systems has an impact on the combustion emission composition as well as the consistency of control strategy and emissions. Understanding the impact of these changes is essential for fuel and fuel additive companies, automotive companies, and aftertreatment developers.

This paper describes the effects of dual injection technology on both regulated and non-regulated combustion emissions from a 2018 Toyota Camry during several cold-start, 4-bag United States Federal Test Procedure (FTP) cycle. Data from the Controller Area Network (CAN) was acquired through the on-board diagnostic (OBD) connector to determine the injection strategy for a 2018 Toyota Camry with a dual injection fuel system. The regulated and non-regulated emissions were also compared to 2017 Toyota Camry emission results with PFI. These vehicles were tested both with and without aftertreatment to continually monitor the relative duty of each injection system.