The VSV is a valve. When open, whatever the vacuum is on the engine side of the valve should equal that on the other side. Make sure the vacuum hoses are not damaged, plugged, etc to limit vacuum.

The computer will open the VSV based on input from various sensors.

For gasoline, if the engine runs OK on the lower octane there is no need to operate at higher. The use of ethanol free fuel may lower N0x.

 

it passed smog
...... barely