Description & Operation

All engines have ignition control systems to lower emission levels, maximize fuel economy and improve engine performance. The system is designed to advance and retard ignition timing as necessary.

All models use a distributor advance with 2 separate vacuum diaphragms. Diaphragm A operates on intake manifold vacuum. Diaphragm B operates on intake manifold vacuum via an inline thermovalve, vacuum control solenoid valve or cold advance solenoid valve. During cold engine operation, thermovalve B allows vacuum to enter diaphragm B to improve engine performance.