F 250 4WD Pickup V8-302 5.0L (1986)
Vacuum Restrictor: Description and Operation
This orifice-type flow restrictor (Fig. 1) is used in several emission calibrations to control the flow rate and/or timing inactions to the following emission
component systems:
a. EGR valve timing-opening and closing.
b. Part throttle spark advance
c. Purge system
d. Thermactor system
