Heat issues. 97 XJ, Flushed core, cable actuated blend door
When I first got my jeep, I barely had any heat. The higher I went in motor settings, the colder it got. So last year, I flushed the core and I had SOME heat, not a whole lot but I managed. This year, the heat was the same and it just wasn't hot enough. I thought maybe the core had plugged up again, so I backflushed it last night, and did a bit of CLR treatment to it. No crap came out of it and the water ran clear pretty quickly. Both the heater hoses are running pretty hot. The top one is 160ish and the bottom is 120ish, according to my cheap infared thermometer.
So, as I was driving around last night being depressed about no heat, I wondered if the cold even worked. I turned it down to full cold and it BARELY changed. And even then, the temp difference could very well be a placebo effect.
I got home and started researching about blend doors and apparently the actuators get stuck pretty frequently after sitting a bit. I bought this Cherokee from my friend who had it sitting for close to a year. Figured it was an actuator and called it a night. This morning at work, I looked to make sure I even had an actuator...where the motor was in the pictures last night, there was just a cable contraption. I didn't get a good look though.
What's the best way to trouble shoot this non-sense?
TL;DR - Flushed, core, no change. Moved heat to full cold, no change in heat. Best way to trouble shoot cable driven blend door?
Went out on my break, turned the knob and watched the cable move and supposedly move the blend door. So the cable looks like its good. Maybe it's time to pull the cable thing and see if the blend door is operating....
Don't hear that...That's what I was listening for last night too, I thought maybe it was just reallllly quiet.
Looking like a blend door.
EDIT: After moving the cable arm back and forth, then leaving it pointed towards the inside of the cab (Heat, i think) it seems to be working better. I flipped it over to cold, and got cold air. Flipped it back to heat, got heat. Put it on level 4 and it got decently warm. Then I put it to cold, heard a POP then it's stuck on borderline heat again. it's hard to turn to cold, but putting it back to heat barely requires any force at all. I'm gonna go mess with it some more, maybe move the arm and hope for the best....then not mess with it. haha.
When attempting to move the arm, it does seem difficult to move. I'm going to disconnect the cable and see if the blend door moves freely. Maybe the cable is bound up somewhere?? I feel this is doubtful because when I had a cohort move the cable, I saw the cable move, but the arm at the blend door wouldn't budge, the cable would just expand outward a bit. Could the cable be so weak that it can't move the arm??
i am having same issue i messed with it last night couldnt figure it out or figure out where some of the stuff was to check at the hump of the floor there is a actuator i messed with but heat is still the same i dont know where the doors are to mess with them but thats what i think my issue is since when i put heat on vents its not even warm at all but if i put it on a split foot and vent it is a little warm at your feet and the higher the speed of the fan the cooler the air gets so i am guessing there is a door stuck!! but where are they and what do i have to do to get access to them? i just got the jeep from a friend and i am not trying to put a lot of money into but i do need heat i dont care if i have to lock doors closed and not have ac and only have heat in winter i am fine with that its just a beater i got for a couple hundred bucks
Well I had a similar problem in the summer, door was stuck routing all air through the heater core, when the vehicle was off the heater valve would open and I would be greeted with a nice blow dryer in an already hot climate. I climbed under there and did some research and zip-tied the door to bypass the heater core.
My cable thing is broken and I plan on fixing that this week some time.
That cable operates this door, (not my pics)
if the door is not the problem check your coolant level. I was trying to figure out why my heater didn't blow hot for a few days. both the hoses where getting super hot but I would only get slightly warm air in the cab. It turns out I was low on coolant, it had enough to barley keep the jeep to temp, but it didn't pass through the heater core.
Edit: Also make sure your heater valve is working.
Hope this helps. . .
92 Cherokee - All nude and in need of some tlc!
Azar, try to disconnect the cable end from the lever on the blend door. Then see if you can move the lever back and forth. Pushing it forward (towards the firewall is full cool. Towards the front seats is full heat.) If it is tough to move, the cable may have broken in its mount behind the control panel. There is a small clip on the cable by the control panel end that goes down into a slot to secure the cable. This clip is removed by squeezing from the bottom to release it from this slot. Do not pry from the top or it will break. Ask me how I know. With the cable secured by the clip, check to see that it moves freely back and forth when you turn the knob.
'97 XJ Moss Green Metallic. 2DR. 2WD AW4 factory tow. General Grabber AT2 255/70x15.