Colony Park V8-302 5.0L VIN F FI (1985)
Fig. 12 Cold engine speed control
Cold engine speed control is accomplished by a throttle stop cam positioner similar to that used on carburetors, Fig. 12. The cam is positioned by a
bi-metal spring and an electric positive temperature heating element. The electrical source for the heating element is 7.3 volts from the alternator which
provides voltage only when the engine is running. The heating element provides the necessary warm up according to starting temperature (cold engine)
and the length of time after starting. Multiple positions on the cam allow for a decreasing cold engine speed to curb idle speed during warm up. The cold
engine speed control also provides an automatic kick down from high cam (fast idle) engine speed to some intermediate speed. This is accomplished
through a vacuum motor and bleed which physically moves the cam a short time after starting the engine.
