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Topic Review (Newest First)
05-09-2011 10:38 PM
dmitchell28
Quote:
Originally Posted by Shelby427 View Post
Sounds for sure like you have a broken door or something is unhooked, to start with.

Always start with the basics. Temp slider does nothing more then open/close a door to allow/block airflow from the blower to the heater core to the ducting. OK engine warmed up, check to make sure both heater hoses are the same temp. If not the core is blocked.

If they are the same temp, most likely the door to the heater core is stuck shut, not allowing hot air into the ducting.


Now for the fan thing, slamming a door shut. We know the upper control is a vacuum and mechanical control.
It mechanically operates one door. Most likely the fresh air/ recycled air function.

The rest of the doors are vacuum controlled to switch the various modes/ vents, defrost,floor, a/c.

The vacuum harness is accessible from inside the glove box opening. It's got a connector you can pull apart. Engine side should have vacuum on at least one line,
(engine running) if it doesn't you have a leak or disconnected line at the engine.

If you have vacuum, then you need to check the various modes operation. The vacuum switch just transfers the vacuum to the hoses that work the other doors. In some cases it runs vacuum through multiple lines, like where you have the switch set for mix, where it blows out the floor and vents. It also operates the door to allow/block airflow from the a/c evaporator into the ducting.

If you have a hand vacuum pump you can use it to work the various hoses to see what does what. If not a simple jumper hose using the engine vacuum will work just as well. Just easier to hear/see a non functioning part or leak, using the hand pump.

Off the top of my head on this part, I'd say you have at least five lines, one vacuum in, and the other four for floor/vent/defrost/ a/c operation.

Vacuum working to the switch and back out on a line, I'd try and follow the lines. Each will lead to a vacuum motor, nothing more then a diaphragm in a small canister.
Vacuum pulls on the diaphragm, the diaphragm pulls on a rod that operates a door.

If you have vacuum to the switch and back out the various hoses, you have these possibilities for inop. Leaks, bad vacuum motor, disconnected or broken rod/door. Also I guess you could have a bad vacuum switch that isn't allowing the flow to the proper doors for vent/floor/defrost.

And yep the 97, least my wife's has sliders not knobs for controls.
This is exactly what I am looking to hear, I am printing this off and checking everything out asap..LOL...thanks alot bud!!! I hope this fixes it, but I still have a few months before it gets cold again..LOL.
05-09-2011 08:41 PM
Shelby427 Sounds for sure like you have a broken door or something is unhooked, to start with.

Always start with the basics. Temp slider does nothing more then open/close a door to allow/block airflow from the blower to the heater core to the ducting. OK engine warmed up, check to make sure both heater hoses are the same temp. If not the core is blocked.

If they are the same temp, most likely the door to the heater core is stuck shut, not allowing hot air into the ducting.


Now for the fan thing, slamming a door shut. We know the upper control is a vacuum and mechanical control.
It mechanically operates one door. Most likely the fresh air/ recycled air function.

The rest of the doors are vacuum controlled to switch the various modes/ vents, defrost,floor, a/c.

The vacuum harness is accessible from inside the glove box opening. It's got a connector you can pull apart. Engine side should have vacuum on at least one line,
(engine running) if it doesn't you have a leak or disconnected line at the engine.

If you have vacuum, then you need to check the various modes operation. The vacuum switch just transfers the vacuum to the hoses that work the other doors. In some cases it runs vacuum through multiple lines, like where you have the switch set for mix, where it blows out the floor and vents. It also operates the door to allow/block airflow from the a/c evaporator into the ducting.

If you have a hand vacuum pump you can use it to work the various hoses to see what does what. If not a simple jumper hose using the engine vacuum will work just as well. Just easier to hear/see a non functioning part or leak, using the hand pump.

Off the top of my head on this part, I'd say you have at least five lines, one vacuum in, and the other four for floor/vent/defrost/ a/c operation.

Vacuum working to the switch and back out on a line, I'd try and follow the lines. Each will lead to a vacuum motor, nothing more then a diaphragm in a small canister.
Vacuum pulls on the diaphragm, the diaphragm pulls on a rod that operates a door.

If you have vacuum to the switch and back out the various hoses, you have these possibilities for inop. Leaks, bad vacuum motor, disconnected or broken rod/door. Also I guess you could have a bad vacuum switch that isn't allowing the flow to the proper doors for vent/floor/defrost.

And yep the 97, least my wife's has sliders not knobs for controls.
05-09-2011 07:50 PM
GreenJack
Quote:
Originally Posted by dmitchell28 View Post
... I guess I need to figure out why its not blowing out hot air also....
Have you tried flushing the heater core? When I purchased mine it didn't have any heat. I flushed the core with CLR and it has worked great ever since....

...
05-09-2011 05:57 PM
dmitchell28 Okay. No water in the floor.....checked cables and they are working. Wd 40 them but it blows out really good on the second setting but as soon as you hit the 3rd setting something slams closed on top and cuts the air off to the whole middle section pretty much. The air still blows hard out of the top side window vent, but actually doesnt come out of vent on the bottom that swivels. But this is just part of my problem, I guess I need to figure out why its not blowing out hot air also.
I have a 97 wrangler, do I have the right heater switch system? it has the slide system on top and bottom. I have seen in a magazine that the one they sell has turn knobs.
05-09-2011 05:31 PM
dmitchell28 walking outside to check everything out right now..LOL
05-09-2011 05:22 PM
Shelby427 Couple of things to check. First look under the dash to see if the controls are actually moving the cables (2) if those appear to be working check for a vacuum leak. Some of the components are vacuum operated. Could be that a door is unhooked/loose/broken inside the case. When you go high blower it's slamming a door shut that is supposed to be open or visa versa.


Also might be a wise idea to flush the cooling system if it's been a while. And while you are at it, reverse flush the heater core. Just pull the two hoses going to it. Shoot water through each hose till it runs clean and strong. A blocked heater core will give heat for a bit, then drop off as what's inside plugs it back up.

I remember the old days with the vacuum operated wipers. LOL! Accelerate and the wiper would stop, leave off the gas and they would work.
05-09-2011 05:03 PM
Jimboo check in front of your passenger-side front seat on the floor, lift up the floor mats... is it wet there at all? or does it look like fluid was/is present?

-jim
05-09-2011 05:00 PM
dmitchell28 I actually just drove it in 90 degree weather with the top down and the AC works awesome, but why cant the heater do the same freaking thing.
05-09-2011 10:17 AM
dmitchell28 when i turn it on high it sounds like its blowing a 1000 mph...and it will actually come out at your feet, but once again, last night it was cold air coming out. Now on that note, on high it will not come out on the defroster and sometimes it wont come out of the middle vents, but it blows hard out of the side vents.
05-09-2011 02:07 AM
Tjae I'm having a similar problem. Last weekend I was coming down to PHX from Flagstaff and had the heater on. When I got close to PHX, it was time to turn on the air, and the compressor kicked on, but the damper didn't switch from heat to cool.

I did get it to go to cool by fooling with it, but wasn't until I got home.

I'm going to replace the temp control switch, to see if that's my problem.

As far as the fan speed control, it could be your switch, or I think the capacitor. I recently replaced my fan speed controller due to medium high going out. It fixed my problem.

Good luck.
05-09-2011 12:21 AM
dmitchell28
Heater Problems!!

Okay, I know I know, its summer, but coming home tonight I realized my heater honestly doesnt work. We drove home to see the family an hour away from home today, the wife and I. It was 90 degrees when we left, so we took the door tops and windows off and left them at the apartment. Well, we didnt leave until after dark, but I was confident that with the heater on high, it would drown out most of the cold air. Well, I was wrong because it wasnt blowing out any hot freaking air!!! needless to say, my wife was pissed.

Okay, I have noticed on high for the AC or the heater, no air will come out of the defroster, but if you drop the speed down to low or next up, some starts to come out. Tonight I turned the heater onto the floor and it was actually blowing out cold air. If I stopped at a gas station it would start to heat up, but I think it was just getting ambient engine temp, because as soon as we started back, it went right back to blowing cold air again. The AC works awesome blowing cold air on hot days. Does anyone have any ideas of what is going on here. I do not want to be caught with my wife freezing again..LOL Someone tell me where to go here! I have noticed that when I turn the defroster on HIGH it sounds like something closes completely up also. Alright, you guys have yet to let me down on here.

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