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The idle air control valve regulates idle speed, not idle condition; as such, I would not consider it a problem at this time.
A way to determine if the EGR or any component or gasket is leaking and causing erratic idle is by spraying choke cleaner on and around it while the condition is present - if idle returns to normal, then you've found the culprit.
Regarding the cruise control surging, the most probable cause is either the magnetic clutch or the motor inside the actuator beginning to fail. As these are not serviced individually, the repair would require actuator replacement.
Looks like you misunderstood my post; I didn't suggest for you to do something while driving the truck. Also, I did suggest spraying choke cleaner on the engine while it was idling, not doing any kind of EGR vacuum test.
I’m sorry, but seeing that we are not communicating, I’ll opt out so others may try. Please do not reply until another expert responds or the site will cycle this request back to me.