buddy has a 1998 Jeep Cherokee, cant get the heater to switch from floor to defrost etc, takes about 5 min to change sometimes it wont at all, esp. when the cruse is on, we think it is a vacuum leak, how can you find this? Ive done carb cleaner for engine vacuum leaks, but been told this isn't a good idea because it deteriorates hoses

THANKS!!

 

https://dodgeforum.com/forumid_52/tt.htm

 

duh thanks

 

sounds like a vac line is leaking