[rpmerf]

Since you got that fancy tool, you might be able to pull the vac lines off one at a time and block off the port with a cap or your finger to see how it reacts. If the speed drops to the desired level, you found your leak.

You can use carb cleaner to find the leak. Watch the A/F and engine speed for a spike. Be sure to spray around the base of the throttle body and the intake ports at the intake gaskets.