Heater hasn't been getting hot at all even on hot days. Blows air but always cool. I've flushed Heater core with air and got some gunk out but still didn't help. Also changed thermostat and heater control valve still did not fix issue. Though I have not made sure it is being activated when turning Heater on. What else can be causing Heater to not blow hot air before I decide to spend $500 to change Heater core or risk doing it myself? Please let me know what you all think, thank you.

What year? Likely older than 97 given you've not deleted the valve yet.
Is your blend door working?
Could even be the blend cable has come off it's little stud

Changing the heater core is no easy quick job

It's a 1996 and I'll definitely have to check that cable in the morning . It's underneath the dash under the heater vent yes?

My XJ had less tan stellar heat when I first got it, so I used a pond pump in a 5 gallon bucket to backflush stronger-than-recommended radiator flush through the core. I let it run overnight like that, replaced the now dirty cleaning solution with new after the first day and let it run for a couple more days just to beat that dead horse.

easy to test with your hands.
Are both hoses going to the heater core the same temp, and what temp?

I'll have to check this today but when I first messed with everything I believe they might have both been only kind of warm, or just the top one was warm i really cant remember, but i am about to go out there and start messing with it again.

Does that cable activate by moving the slider from cold to hot or is it something else? I hear a change in air flow when going from cold to hot but still doesn't get warm

Top hose is warm and bottom hose is pretty hot compared to the top
but I just noticed both hoses going into the heater control valve are really hot but not the hoses from the hcv to the heater core

can you tell if the HCV is opening all the way?

I'd ditch that POS right now anyway.

yeah ive seen alot of people saying that, i definitely should remove it either way. But I'd like to have someone there with me to turn it on and off while I watch but might not be til later

Worth a check to eliminate!

( mine is a RHD so its on the left)
But post #1 in the below thread will explain where to find it. Not sure if the same for your 96 since those always appear different but someone might chime in in regards to that or you can find out.

https://www.cherokeeforum.com/f2/eas...ailure-225063/

Just checked now and when switching to heat it is definitely pulling the cable still

Double checked hcv and when heater is off the pin is all the way in and when I turned heater on it fully came out. Is that how it's supposed to be or is it supposed to be flipped?

This is my hcv

The only hose that is not hot is the top hose of the heater core to the bottom of hcv