One embodiment of the present invention is an apparatus including an internal
combustion engine for powering a ground travelling vehicle, a throttle control
arrangement including a device for sensing position of an operator-adjustable pedal
to provide a throttle control signal, a first sensor to sense rotational speed
of the engine, a second sensor to sense brake status of the vehicle, a way to determine
failure of the throttle control signal, and a way to operate the engine in a limp-home
mode in response to the failure, which includes fueling the engine during the limp-home
mode of operation in accordance with idle position of the pedal, rotational speed
of the engine, and the brake status.