2002 3.7 liberty & heater & ac

[Logan Savage]

I bought this vehicle with a rod knocking . I installed a crank kit & the engine is fine . No back history on this jeep .
I've now found the heater blows barely warm & the ac blows barely cold . I've read many threads about blend door problems & clogged heater cores .
The heater fan blows fine & switches to whatever vent I move the selector knob to . The air is barely warm when the heat / cold knob is turned to hot & blows cool when the knob is turned to cold . Both of the hoses going to the heater core get hot .
Before I attack this problem I'd like to know if a blend door problem could cause a barely warm heater & a barely cool ac ? These could be two completely different problems but I'd like to know if one problem can cause both . The ac does have a charge in it .
I have a recall notice that will require a visit to the dealership . Can the dealership check for proper operation of the blend door / doors with a scan tool ? How many blend doors are there ? TIA

I know many people visit multiple forums but I'm going to post this on another forum anyway .

 

[ltd02]

I saw the post on the other forum too. I'll say that's exactly what mine did when the blend door actuator motor failed. It would only run in one direction and even when it worked sporadically as soon as you shut down I think it defaults to cold and there it stuck. I would try the mentioned re-calibration first but if it fails I'd try to see if you can hear the blend door actuator working. It's usually pretty quiet but even the replacement can be heard if you listen closely. It is a PITA to get to but I posted a how to a while back.

http://www.jeepkj.com/forum/f202/how-replace-hvac-blend-door-actuator-59206/

Hope your crank kit works out. I just put one in my 02. Hoping to drop the motor back in this weekend. Have to fix a stripped oil pan bolt hole first. Seem to have been cross threaded from the factory.