Means for disabling an automobile by causing an on-board computer to disable the ignition system thereof. A radio receiver provides a signal to the on-board computer through an existing port (e.g. diagnostic port or ignition interface port). The on-board computer disables ignition function through supplanted firmware that recognizes the status of the signal received from the radio receiver. Removal of the radio receiver also disables the ignition system. The entire system is installed during government required inspections (e.g. a smog check).