Cold Starting System

During cold starting, additional fuel is injected into the intake manifolds by 2 cold start injectors. These injectors are controlled by the cold start relay and the thermo time switch.

The thermo time switch senses engine coolant temperature, and depending on temperature makes or breaks the ground circuit of the relay. When the starter is activated, the cold start relay is energized with the ground circuit being completed by the thermo time switch.

The thermo time switch also limits the time that the relay is energized (12 seconds max.). The enrichment provided by the cold start system is in addition to the enrichment resulting from the coolant temperature sensors' signal to the ECU.

If the temperature at the thermo time switch is above 95°F (35°C), the thermo time switch will not close and no cold start enrichment will take place.