Fuel pressure regulator vsv?
Correct. It increases fuel pressure load. The broken port had a small air filter on it. As the VSV (vacuum switching valve) opens and closes it pulls air through that port. Not having the filter can cause junk to enter the valve.
Here is the story on the valve direct from Toyota:
"Fuel Pressure Control. The ECU sends signals to the fuel pressure regulator VSV to increase fuel pressure based on intake air temperature, coolant temperature and starting signal. By this system, engine restartability is maintained when the engine is hot. When restarting a hot engine, the ECU increases the fuel pressure above the normal level to reduce the fuel tendency to percolate. This helps restarting and also maintains the engine idle stability. The controlled fuel pressure is 21.2lb/in2."
"Operation. When the coolant temperature switch is ON (above 221*F) or higher, if the engine is cranked, the ECU turns on the VSV. As the VSV goes on, atmospheric air is introduced into the diagram [sic] chamber of the pressure regulator and the valve closes the passage. The fuel pressure becomes higher than the fuel pressure under normal driving condition by the amount of the intake manifold vacuum only. Even after the engine is started, the VSV remains on for several seconds."
So, it sounds like if you are not having restart issues, you can abandon this valve. Personally, I would keep it, though in your case, replace it.
