Gasoline direct injection (GDI) engines have been developed rapidly in recent years, driven by stringent legislation requirements on vehicle fuel efficiency and emissions. However it faces the great challenge of particulate emissions especially when the injector deposits are formed. The gasoline fuel in Chinese market basically contains no detergents but high levels of aromatics and olefin components, which makes it easy to accumulate the injector deposits affecting the engine performance and emissions. To solve this issue, the gasoline with detergents is a viable solution. In this study, a 1.5L turbocharged GDI engine developed by a Chinese manufacturer was selected to investigate the injector deposit formation and its impact on engine performance and emissions. The test was then repeated by using gasoline with detergents provided by Shell to research the effect of detergents on the mitigation of injector deposits. It was found that even a small amount of injector deposits may have a great effect on particulate emissions. The gasoline with detergents was proved to be effective to reduce the formation of injector deposits.