Heater core going out?
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Heater core going out?
Ok, every once in a while (after I've run the car for a while, park it for a few minutes after having run the A/C, and then start her up again without the A/C) I get fog on the windshield for about 20 seconds. It goes away once the moisture is out of the system.
From what I've heard from you guys, this is a sign of the heater core starting to head south.. right? It's just someday going to blow steam out everywhere, right?
[Modified by Glock'94, 2:40 AM 8/9/2001]
From what I've heard from you guys, this is a sign of the heater core starting to head south.. right? It's just someday going to blow steam out everywhere, right?
[Modified by Glock'94, 2:40 AM 8/9/2001]
Le Mans Master
Joined: Jul 1999
Posts: 7,072
Likes: 4
From: Maryland
Re: Heater core going out? (Glock'94)
On sharks that's usually the tell tale sign (don't know enough about C4s yet to say), however I have also noticed in other cars ('95 Rustang GT) that it did that on occasion. I believe it was condensation on the cold parts whcih when you started it back up blew fog. If it hadn't been sitting long enough they were still damp and sweaty. I was able to turn the AC off and just run plain air to warm up the ducts before parking it. Then on restart it didn't fog. If it's the heater core you should smell antifreeze. Of course that could have been the entirely wrong diagnosis and the poor kid who bought my Rustang is in the midst of a heater core replacement about now. :D :D :jester
Thread Starter
Team Owner
Joined: Apr 2001
Posts: 22,267
Likes: 3
From: Dallas TX
Re: Heater core going out? (Glock'94)
Hmm.. sounds like the AC moisture is just staying in there and coming out when I start the car back up. There is no smell of antifreeze at all (good sign :hat ).
Race Director
Joined: Jul 2001
Posts: 14,604
Likes: 3
From: Glendale, AZ
Re: Heater core going out? (Glock'94)
my turn, my turn....i don't even have water running through my heater core, i lost it around the fourth of july......and it still hasn't been changed, and i still get steam (not much) and hot damp air out of the AC at startup. so there may be more than that wrong?!?!?! i sure hope not for me...and especially you, seeing as you haven't had the core go out yet.....if i find out anything else, i will repost
Le Mans Master
Joined: Dec 2000
Posts: 7,839
Likes: 22
From: San Diego, Ca
Re: Heater core going out? (85_togo)
Make sure the weep hole below the evaporator housing isn't plugged. It's a little difficult to find, but you should be able to feel it under there. You can take a tooth pick or something soft (don't use anything that might puncture the evaporator), to make sure it's completely opened and allowing the moisture to drain off.
Melting Slicks
Joined: Jun 2000
Posts: 3,215
Likes: 6
From: Tampa Florida
Re: Heater core going out? (SunCr)
I've had the condensation on several cars, none with heater cores failing. I know mine were normal. I believe it is just humidity in the system...
Now if you have oily residue on inside of windshield or the antifreeze smell or wet passenger footwell then you have a problem.
Now if you have oily residue on inside of windshield or the antifreeze smell or wet passenger footwell then you have a problem.
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Safety Car
Joined: Mar 2000
Posts: 3,620
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From: Hillsboro OR
Re: Heater core going out? (Glock'94)
I have had this happen also. Its usually after rain and very humid outside. My guess is that the windshield is cooler than the air in entering the interior of the car and causes condensation to form. It only happens when humidity is high. I would think it would happen on dryer days if the heater core is bad.
