Wagoneer L6-258 4.2L VIN C 2-bbl (1982)
Pressure Feedback Exhaust Sensor: Description and Operation
Fig. 20 EGR dump valve
This valve, Fig. 20, is used on some vehicles and is connected between the EGR vacuum signal source and the EGR valve. It prevents EGR
operation when intake manifold vacuum drops to 3-5 inches Hg, by "dumping" the EGR vacuum signal.