F 250 4WD Pickup V8-460 7.5L (1984)
Ignition Timing Connector: Testing and Inspection
Ignition Timing Vacuum Switch
Ignition Timing Vacuum Switch Test Chart
1.
Disconnect switch from ignition module.
2.
Connect suitable ohmmeter across switch terminals and compare resistance measured to ``less than'' values in the Ignition Timing vacuum Switch
Test chart.
3.
Apply vacuum to switch, using an outside vacuum source. Compare resistance now measured across switch terminals to ``greater than'' values in
the Ignition Timing vacuum Switch Test chart.
4.
Replace switch if resistance is not within specifications.