Feb. 11, 2020—Nearly every automaker has direct-injection technology in their latest engines. The controlled bursts of gasoline spray directly into the combustion chamber are supposed to lead to more efficient burning and, thus, greater fuel efficiency.
As NOLN has explored quite a bit, the early challenges for direct injection came with extra valve deposits. Now a new issue has emerged that presents concern about what's coming out of the engine, rather than what's inside.
A Green Car Reports story says that a recent study suggests that direct injection engines produce more black carbon aerosols, which could add to atmospheric warming. The short-term "social cost" effects of the aerosols could outweigh the long-term emissions saved through efficiency, the study says.
The story notes that while automakers like Mercedes-Benz and Volkswagen have tried to incorporate particulate filters into the exhaust system, that may reduce the fuel-efficiency gains desired in the first place.