Time for a new carburetor?

Assuming there is no vacuum leak....it probably just got some crud in it again. Sometimes it doesn't take much. First, remove the idle mixture screw and blow compressed air into the hole...then reinstall the screw. See if it will idle now. If yes, I'd carefully pop the top off the carb(or side as the case may be) and blow out the float bowl and idle circuit with some compressed air. Reassemble and see how it goes.