AC is blowing Hot???
Thread Starter
Safety Car
Joined: Jul 2000
Posts: 3,596
Likes: 37
From: Orange County CA
AC is blowing Hot???
My 99 (with Dual AC) has developed an intermittent AC Problem. Most of the time the AC works fine…but for some reason the AC intermittently blows HOT. If I turn the AC Control **** all the way down it often (but not always) causes the AC to blow cold. But when I start raising the temp by just a few degrees it starts blowing cold. I checked the DTC codes and there are no HVAC Codes…but there are some codes for the IPC, LDCM, RDCM and SCM.
Any Ideas???
Thanks for the help.
Any Ideas???
Thanks for the help.
Instructor
Joined: Jul 2006
Posts: 174
Likes: 4
From: West Palm Beach Fl
Dude I am having similar problems. My drivers side now is blowing hot and the passenger side is blowing cold. I have a 98 with basic controls, not digital.
Checked the compressor and it is kicking on. I hope we could both get some help on this.
Checked the compressor and it is kicking on. I hope we could both get some help on this.
Last edited by Guro305; Sep 8, 2006 at 03:32 PM.
Le Mans Master
Joined: Aug 2005
Posts: 7,392
Likes: 216
From: Merritt Island, FL
Most common explanation is low refrigerant. Get a refrigerant gauge, hook it up to the low pressure side, run the AC, and see if your system is low. Then, the question becomes *why* is the system low.
I had the same problem, which eventually progressed to a complete lack of cooling on either side. Leaking condenser, shot compressor (though it still ran!). Still hurting from the bill on that deal
Good Luck,
Andrew
'01 Triple Black Vert Z51
I had the same problem, which eventually progressed to a complete lack of cooling on either side. Leaking condenser, shot compressor (though it still ran!). Still hurting from the bill on that deal
Good Luck,
Andrew
'01 Triple Black Vert Z51
Le Mans Master
Joined: Aug 2005
Posts: 7,392
Likes: 216
From: Merritt Island, FL
The seals were shot, it was leaking refrigerant and dye all around the front and rear of the compressor, and I'm assuming that some of the internal seals/rings were bad as well, So apparently it wasn't pressurizing the system adequately.
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Burning Brakes
Joined: Aug 2000
Posts: 889
Likes: 0
From: DFW tx
There are quite a few reasons why it would blow hot, head units, actuator doors, vacuum lines disconnected, low freon, etc.
My '98 was blowing hot from drivers side and cool from passengers side, sometimes both would blow cool. I had the freon recharged, I was down .75 which is about 40% low. The shop wanted to charge me $1000 plus to fix it, but that is another story. I told them just to fill it back up.
Long story short, the recharge fixed my issues and it has blown full cold from both sides ever since (6 months).
My '98 was blowing hot from drivers side and cool from passengers side, sometimes both would blow cool. I had the freon recharged, I was down .75 which is about 40% low. The shop wanted to charge me $1000 plus to fix it, but that is another story. I told them just to fill it back up.
Long story short, the recharge fixed my issues and it has blown full cold from both sides ever since (6 months).
Instructor
Joined: Jul 2006
Posts: 174
Likes: 4
From: West Palm Beach Fl
Hey guys, before I go get a reading tomorrow, what is the correct psi or the correct range of the psi for the a/c? Also, not to sound stupid because I never bothered to look, but is the low side clearly marked and if not, which one is it?
I'll keep you guys updated.
I'll keep you guys updated.
Le Mans Master
Joined: Aug 2005
Posts: 7,392
Likes: 216
From: Merritt Island, FL
The low side is just inboard of the battery area -- it's the larger diameter aluminum tubing. Not sure about actual pressures, though... some of the cheapo gauges have the appropriate ranges marked on them.
Thread Starter
Safety Car
Joined: Jul 2000
Posts: 3,596
Likes: 37
From: Orange County CA
Originally Posted by harrell3us
Mine did the same thing. It was the climate control. $500 later, it works. Had to replace the whole module.
Ouch! That seems like a likely candidate to me. My issue isn't a hot on one side and not the other. The car sometimes just chooses to blow hot....and I mean really hot...like the heat is on high. I tried directing the flow to the floor, then the vents, then the defrost. Same condition....full Hot. If i turn the control all the way down to the coldest setting it starts blowing cold again. Very strange.
Racer
Joined: Oct 2004
Posts: 370
Likes: 1
From: Tracy CA
A/C intermittent
The A/C in my 2001 just started intermittently working. Some days it will blow cold, other's it will just blow whatever the outside temp. is (hot). I can still turn the heat up hotter, but can't get it to blow cold when I want.
Dealer says I need a new A/C Control Head, part no. 10345293. Hope yours is something cheaper.
-Rick
Dealer says I need a new A/C Control Head, part no. 10345293. Hope yours is something cheaper.
-Rick
Instructor
Joined: Jul 2006
Posts: 174
Likes: 4
From: West Palm Beach Fl
Update!
I unplugged the battery and nothing. I hit the lowside with the gauge and it read fine. Once I started up the car and hit the gauge, it was obvious what the problem was. A can of freon later and alas.........ICE COLD A/C!
Last edited by Guro305; Sep 9, 2006 at 08:19 PM.
Racer
Joined: Sep 2006
Posts: 260
Likes: 1
From: Chesterfield MI
Originally Posted by Charley Hoyt
Ouch! That seems like a likely candidate to me. My issue isn't a hot on one side and not the other. The car sometimes just chooses to blow hot....and I mean really hot...like the heat is on high. I tried directing the flow to the floor, then the vents, then the defrost. Same condition....full Hot. If i turn the control all the way down to the coldest setting it starts blowing cold again. Very strange.
It seems to me that the vacuum operated switch that shuts off the flow to the heater core is sticking. I have had this happen before and it can drive you crazy being that it is intermittent. Check it out!
Ray
Thread Starter
Safety Car
Joined: Jul 2000
Posts: 3,596
Likes: 37
From: Orange County CA
Originally Posted by Guro305
I unplugged the battery and nothing. I hit the lowside with the gauge and it read fine. Once I started up the car and hit the gauge, it was obvious what the problem was. A can of freon later and alas.........ICE COLD A/C!
That's not good. Freon does not wear out or get used up....if you need freon...you have a leak somehere.
Instructor
Joined: Jul 2006
Posts: 174
Likes: 4
From: West Palm Beach Fl
You are right. Used freon with stop leak/leak tracer to much success in the past. I tried it now and didn't see any of the leak tracer spill out anywhere.
In my experience that's usually a good sign because the leak is very very small. I'll leave it be until it, if it, runs out again. Sorry if I'm one of those "worry later" kinda guys!
In my experience that's usually a good sign because the leak is very very small. I'll leave it be until it, if it, runs out again. Sorry if I'm one of those "worry later" kinda guys!
