The system has an injector (14) comprising a workspace (18) containing filled-water in normal operation. The workspace is in flow connection to a valve (16) of the injector. The valve releases or closes a flow connection from the workspace to an injection region (12). The workspace is partially filled with gaseous mixture when an internal combustion engine is switched off. A return flow option from the working chamber to a reservoir (22) and the valve is opened to the injection region when the internal combustion engine is switched off. An independent claim is also included for a method for operating an injection system.
