System description To ensure the vehicle can still be driven to the nearest workshop in the event of one or several sensors failing, an emergency drive function is integrated in the control unit. The idle speed is exactly maintained by means of the idle speed governor as long as the engine output is sufficient for this. The regulated idle speed can be altered within certain limits. The idle speed set ex works is 600 rpm. However, it can be varied via the EDC op- erating element in the range from 600 to 750 rpm. Starting-fuel delivery is output when either a lower start recognition speed is exceeded.
The starting-fuel delivery and cold idle speed are limited as a function of the coolant tem- perature to avoid impermissible smoke emission and unnecessary revving of the engine after starting. 9