Quote:

If the carb is adjusted right; meaning that the the throttle blades are in the correct position for idle, then the power circuit (including the power valve) does not see any vacuum signal at idle.

Now, if the throttle blades are open too far, then the power circuit could be starting to activate. But that situation needs to be fixed first.



The power valve always has intake vacum to the backside of it.
Sounds like you mean to say if the throttle valves are open to far then the main metering system may start drawing fuel into the venturi if air flow is starting to go thru the venturi. Ron