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Heater core going out?

K

Kats66Pny

Active Member
This morning I was on my way to take my daughter to school, and we heard a weird popping-like noise behind the dash on the passenger side. I turned the radio down to hear it, but didn't hear it again. Dropped daughter off at school and on my way home I heard the noise again. I also noticed the air blowing on my feet was blowing hot, then cold, the hot, cold, hot, etc.

I'm guessing the heater core is in the same place as it would be in a classic mustang? That's where the noise seemed to be coming from, and the fact the air was changing back and forth from hot to cold makes me think it's going out.

I swear I just don't have the best of luck when it comes to Mustangs. :wtf

First the water pump failed and had to replace it.
Then it started over heating again and turns out the intake is leaking (slowly). I'll have to replace that soon.
Friday on my way to pick up my daughter from school I got a flat tire. Worst part was the lug nuts were on so damn tight I couldn't get them off so I had to call my buddy with the tow truck to come help me change a tire! Felt like such a 'girl'. :bomb Luckily he had a cordless impact and was able to get the lug nuts off. On the bright side, since the tire blew, I was able to convince hubby to get me 4 new tires. Lower profile, and slightly wider in the rear.

Now this? :rant
 
Yes it's in the same location.
Sounds like a control issue and not the heater core actually leaking.
You didn't say you smelled coolant, which is really unmistakeable, so that's a good thing.
Popping concerns me since electrical issues could cause popping, or arc-ing, which is potentially a fire hazard.
I'd suggest just pulling out the glove box (easy to do) and looking at all the connections, both electrical and vacuum, making sure each is tight and in good shape.
Give us a followup please.
 
Since you mention recent water pump work and an intake leak, I'd bet on an air bubble...
 
The water pump was replaced back in end of July, early August. Would there still be air bubbles? Of course I haven't ran the heater until recently - starting last week, when it was cold in the morning and need to defrost the windows.
 
"BobV" said:
Since you mention recent water pump work and an intake leak, I'd bet on an air bubble...
Click to expand...
that's what I was thinking too but I don't know about the popping sound.
 
Could be the blend door motor or the controls to the blend door motor. The blend door is a door inside the heater box that controls the air flow. Lets the air flow either through the heater core or from fresh air or a blend of both. When its acting up, try switching from hot to cold or cold to hot and see if the noise stops.
 
"RyanG85" said:
Could be the blend door motor or the controls to the blend door motor. The blend door is a door inside the heater box that controls the air flow. Lets the air flow either through the heater core or from fresh air or a blend of both. When its acting up, try switching from hot to cold or cold to hot and see if the noise stops.
Click to expand...

This is my guess as well. When the blend door actuator fails, the door flaps open and closed repeatedly. If it won't stop, there's a connector you can unplug to stop it until you get it fixed.

Frank
 
I had the blend door issue on my Expedition. The actuator defaults to defrost (spring loaded) the vacuum has to overcome the spring to make it open. How does the Mustang work?
 
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