So I just bought an 89' Jeep Cherokee and I am having issues with my heater blowing out any other vents than just the defrost vents on the top of the dash.. What would cause this and how do you fix it?

 

On the passenger side inside of the bumper there is a bottle that holds vacuum for the vents to work. If the vacuum hose going to that is broken it will cause the defrost only problem. Look from the fire wall out to the bottle and see if there are any breaks in the line.

 

Thank you... Do you know where I can find a diagram or something I can follow to get my vacuum lines in where they should be? My vacuum ball is dangling by a ziptie... I found it but it's in rough shape...
Thank you in advance.

 

had the same issue here the diagram of the vacuum system.

 

You are a life saver!! Thank you, I could not find that to save my life!!