Operation CHARM: Car repair manuals for everyone.

Vacuum Advance Cut-Out System

Fig. 8 Deceleration fuel injection cut-out system:





The distributor vacuum advance unit is subjected to manifold vacuum. When the throttle is at idle position, the micro switch closes and energizes the twin speed relay, Fig. 8, grounding the electro valve which connects the vacuum advance circuit to the atmosphere.


Fig. 8 Deceleration fuel injection cut-out system:




Fig. 11 Disconnecting T-hose from electro valve:




Fig. 12 Connecting vacuum pump to electro valve:






Diagnosis

1. Disconnect T-hose, Fig. 11, from electro valve.
2. Connect a suitable hand held vacuum pump, Fig. 12, to the electro valve.
3. Start engine and increase engine speed slightly. Pump gauge should indicate vacuum.
4. Release throttle and allow engine to return to idle. No vacuum should be indicated.
5. If vacuum is obtained with engine idling, check condition and/or adjustment of micro switch, operation of twin speed relay, Fig. 8, and electro valve.