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Home >> Volkswagen >> 1985 >> Vanagon F4-1915cc 1.9L >> Repair and Diagnosis >> Powertrain Management >> Ignition System >> Distributor >> Distributor Advance Unit >> Testing and Inspection >> Checking Centrifugal Advance >> With TDC Tester
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With TDC Tester



Ignition distributor, checking centrifugal advance with TDC sensor

CAUTION: Ignition must he switched OFF before connecting tester.





- Connect tester according to manufacturer's instructions.
- Connect positive lead to alternator or connection box.
- Pull both hoses off distributor vacuum unit.
- Disconnect plugs from idle stabilizer and connect together.
- Start engine and adjust idle speed to 900 RPM.
- Note basic advance angle shown on tester.
- Increase engine speed slowly. centrifugal advance is indicated by an increase in the number of degrees.
- Increase engine speed to next test speed.
- Read advance angle on tester.

Note: To determine centrifugal advance, subtract basic advance angle from last advance angle measured.
Example last advance angle measured (-) minus basic advance angle (=) centrifugal advance

- Compare centrifugal advance angle. to specified value on specification chart
- Repeat test at other test speeds.
- Reconnect vacuum hoses when completed testing.
- Adjust idle speed.