Methods and systems are provided for continuously estimating a direct injector tip temperature based on heat transfer to the injector from the cylinder due to combustion conditions, and heat transfer to the injector due to flow of cool fuel from the fuel rail. Variations in the injector tip temperature from a steady-state temperature are monitored when the direct injector is deactivated. Upon reactivation, a fuel pulse width commanded to the direct injector is updated to account for a temperature-induced change in fuel density, thereby reducing the occurrence of air-fuel ratio errors.