System Operation

When the ignition is turned to the start position, current flows to the starter motor and the thermo-time switch.
If the engine is cold (below 113°F/45°C), the thermo-time switch completes the circuit. The cold start valve receives current from terminal 16 on the starter motor, and, when grounded by the thermo-time switch, operates, enrichening the fuel mixture when the starter motor is engaged (nine seconds maximum).
When the ignition is in the run position, current flows to the fuel pump relay via fuse 22. The relay operates and the fuel pump starts to run. Current also flows through the heating coils in the auxiliary air valve and the warm up regulator.
Ignition pulses are sent from the ignition pulse amplifier to the fuel pump relay and the Lambda system. If the engine stops, stopping the pulses, the relay is de-energized, shutting off the power supply to the fuel system.
The Lambda system incorporates an oxygen sensor, which provides continuous input to the ECU about the amount of oxygen in the exhaust gas. On the basis this and the inputs the ECU receives from the other sensors and relays, the modulating valve regulates the amount of fuel being injected.
During the starting phase, the time relay receives control voltage when the ignition switch is in the start position and boosts the supply of fuel via the ECU and modulating valve.
The thermostatic switch senses the engine coolant temperature and opens when the temperature is higher than 77°F (25°C), breaking the circuit to the cold start valve.
The fuel booster switch is used to control the fuel boosting during acceleration. When the engine is cold, the switch opens the cold start valve. When the engine is hot, a signal is sent to the time relay, which boosts the supply of fuel via the ECU.