Weird Electrical Issues Seemingly Unfixable

[George_San_Jose1]

fyi, a discussion on the early 90’s Corolla’s EGR configuration for comparison. It seems like it is pretty similar to Ford’s method used on your Ranger

Corolla EGR System

Just trying to understand how the egr vacuum switching valve works. 4afe engine, 92 Corolla. It says the ECM opens the vacuum passage of the vacuum switching valve and vacuum is not transmitted to the EGR valve, but vented to the atmosphere, causing the EGR valve to stay closed when coolant temp is low or at idle position or engine is at full throttle. Would you say the VSV is shown in the closed or open state? Is the VSV solenoid powered or not in that state? Why does the egr valve have …