Systems and methods for electronically controlling the fuel-to-air ratio of a fuel mixture supplied to an internal combustion engines are disclosed. In one aspect, electronic control systems and methods are provided that determine and automatically move a choke valve in accordance with a first ramp having a first characteristic that is dependent on engine temperature and ambient air temperature. In another aspect, an integrated ignition and electronic auto-choke module is provided. In yet another aspect, electronic control systems and methods are provided that dynamically control a movement characteristic of a choke valve using a feedback loop.