Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Distributor Vacuum Control: Description and Operation
Forward Delay Valve
PURPOSE
Some engines incorporate a one-way forward delay valve in the vacuum advance circuit to reduce hydrocarbon emission and improve driveability.
OPERATION
The valve delays the effects of sudden increases in vacuum during rapid throttle closings. This action prevents sudden spark advance during
deceleration.
