System Testing: Starlet
- Connect a vacuum gauge to distributor main diaphragm hose and another vacuum gauge to distributor sub-diaphragm hose.NOTE: If your vehicle is equipped with high altitude compensation system (HAC), disconnect lower vacuum hose of HAC valve and connect it directly to intake manifold before testing spark control system.
- Check that coolant temperature is below 106°F (41°C). Start engine. Check that main diaphragm vacuum gauge indicates zero and sub-diaphragm vacuum gauge indicates steady vacuum when engine is accelerated or running at idle.
- Warm up engine to normal operating temperature. Check that main diaphragm vacuum gauge indicates zero at idle and high vacuum when engine is accelerated. Check that sub-diaphragm vacuum gauge indicates high vacuum and fluctuates when engine is accelerated from idle.
- Remove distributor cap and rotor. Apply vacuum to diaphragms checking that vacuum advancer moves. Reinstall cap and rotor. If system performed as described, testing is complete. If not, check individual components as necessary.