Spark Timing Control System: Description
The spark timing control system aids in reduction of exhaust emissions by delaying spark port vacuum to distributor vacuum advance unit during acceleration. On 2.0 Liter engines, the system consists of a vacuum delay valve, which is located in line between carburetor and distributor (Federal) or between thermo valve and distributor (Calif.). On 2.3 Liter engines (Calif. Only), the system consists of a vacuum delay valve (Man. Trans. Only), and a distributor solenoid valve installed in line between intake manifold and distributor. The distributor solenoid valve is controlled by a timer and thermo switch.