01' Cherokee. Heater and air conditioner only blow on top vent/ defrost not matter what setting it on? Any ideas on how to fix it? or Whats wrong?

 

vacuum leak in lines or vacuum ball not holding vacuum

 

Vac related as already mentioned.

I was missing the vac ball/tank, so I just capped the line with a screw and it seems to have fixed my issue completely.

 

Hmm... Any way u could help me to find where the line is? or how to tell?

 

inside of front bumper on pass side there should be a black ball about the size of a soft ball it has 2 line on it one comes from motor area and supplys vacuum the other goes to th area under hood at fire wall on pass side it runs unde bat along fender aera to fire wall a lot of times the tube is rotted under bat from bat corrosion getting on it check both line from end to end if broke get rubber hose and cut out affected aera

 

looks like this you dont need to pull bumper to get to it get at it thru inner fender

 

alright that helps a lot. Thanks, time to get to work. hope thats it

 

so good call on it being my vacuum line. i looked around and didnt see any leaks but i followed the line to my motor and saw that it has disconnected. all fixed now. thanks for the pointers

 

beers on you