hi guys , im having heater problems wiith my 93 f150 ,if the truck is off it will only blow out defrost, if i start the truck it will work out both vent and defrost but no floor or mix? i have replaced both vacum motors under the dash ,and ran a new white vacuum line by the heater core , im wondering if there are other vacuum lines to check or if the actual controller is messed up? i know i used to be able to control it with the truck not running?thanks

 

Sounds like a bad vacuum line to me.