A/c issue
Senior User
Joined: Nov 2004
Posts: 357
Likes: 0
From: Lancaster, PA
Put a thermometer in the vent. If it reads higher than ambient you are getting heat from the heater core. Clamp off any heater hoses going into the firewall and see if the air temperature drops.
If that isn't the case then you have a pressure problem in the freon loop.
If that isn't the case then you have a pressure problem in the freon loop.
Hotshot
Joined: Jul 2005
Posts: 11,931
Likes: 180
feel the two air conditioner hoses / lines under the hood... one HOT, one COLD... maybe even some ice on it on a hot day... If the AC is working ( hoses hot and cold) and all you get is hot air, then your blend door is broken and all the air is going thru the heater core
Fleet Owner
Joined: Apr 2008
Posts: 24,316
Likes: 5,127
From: 0,0,1
If you move the temperature control from cold to hot and back again does the temperature change, or do you hear any clunks from the dash?
Hotshot
Joined: Jan 2004
Posts: 19,760
Likes: 1,079
From: St Louis
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5th Wheeling
Joined: Jan 2003
Posts: 39
Likes: 1
From: Venedy Illinois - USA
I have the same problem, the ac will be working and i’ll Hear a clunk and all of a sudden only hot air comes out. I move the control from cold to al the way hot and then back again to all the way cold and cold air comes out. So whats the deal? Mine is a 97 5.4 xlt .... sorry about the duplicate post, my Ipad doesn’t like this webpage.....
Last edited by wojolsc; Jul 31, 2018 at 09:49 PM. Reason: Added year
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5th Wheeling
Joined: Jan 2003
Posts: 39
Likes: 1
From: Venedy Illinois - USA
I have the same problem ... cold air will be coming out then all of a sudden i will hear a clunk and i will be getting full hot air. I turn the temp control **** to full hot then back to full cold and cold air comes out again..
Fleet Owner
Joined: Apr 2008
Posts: 24,316
Likes: 5,127
From: 0,0,1
Your blend door is broken.
5th Wheeling
Joined: Jan 2003
Posts: 39
Likes: 1
From: Venedy Illinois - USA
Oh well, I watched 3 YouTube videos on it and it seems like it will be a Saturday morning project for some future Saturday..... I always wanted a dremal tool anyway. Right now it will stay cold as long as i put it all the way cold and don’t mess with it. I have three other car projects ahead of it
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