ADV1 - Check Vacuum Supply

^ Check the vacuum hoses to the distributor diaphragm for cracks or poor connections.

^ Remove the vacuum delay valve.

^ Using a Rotunda Vacuum Tester 021-00014, or equivalent apply 635 mm-Hg (25 in-Hg) of vacuum to the green side of the valve.

^ Does the vacuum delay valve hold vacuum for 10 - 2O seconds?

YES -- Go to ADV2. ADV2 - Inspect Timing

NO -- Service hose as required or Replace the vacuum delay valve.