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What the heck is this under the glove box?!

  • Thread starter Thread starter psmithstang
  • Start date Start date Jun 12, 2011
P

psmithstang

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Jun 7, 2011
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Jun 12, 2011
#1
  • Jun 12, 2011
  • #1
Hey,

Got a 91 GT I just picked up. Still getting to know the car. Can anyone tell me what this box is under the passenger side of dash just below the glove box? It looks like a filter of some sort. Also it seems like there is something oily oozing out of the seems. Thoughts? How to replace? cost? let me know. Love the help. many thanks.
 

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Rick 91GT

Mustang Master
Nov 29, 1999
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Jun 12, 2011
#2
  • Jun 12, 2011
  • #2
Thats part of the heater/ac box.. Is the fluid antifreeze? Is the carpet wet?
 
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psmithstang

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Jun 7, 2011
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Jun 12, 2011
#3
  • Jun 12, 2011
  • #3
yup carpet was a little damp. Thought that was from the leaky sunroof, but makes more sense to be from this. Fluid on seems of the box was a little oily. Carpet. What should i do?

Thanks for your reply.
 

Rick 91GT

Mustang Master
Nov 29, 1999
9,692
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PA
Jun 12, 2011
#4
  • Jun 12, 2011
  • #4
Usually that means the heater core is leaking, if your mechanically inclined you can swap it out, its not hard, but its not easy....
 
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psmithstang

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Jun 7, 2011
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Jun 12, 2011
#5
  • Jun 12, 2011
  • #5
Thanks again for your help figuring this out. Seems like its the heater core. I found a good blog from Late Model restoration that explains how to replace it, its a very detailed breakdown. Not sure I can do it, but if anyone else is interested to try themselves, its a great detailed post...

1979-93 Mustang Heater Core Replacement - LRS Blog - Read Here Shop Here
 

larrym1961

5 Year Member
Dec 18, 2010
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Idaho Falls Id
Jun 12, 2011
#6
  • Jun 12, 2011
  • #6
I had to replace a heater core on my '87. it took me about 5 hours to do. Start to finish. It really was not a bad job. but then again I built and did my own engine swap, AOD to 5 speed conversion and rear gear swap. So a good bit of mechanical skills does help.
 

f8tlfiveo

My wife likes my spool and blow-off valve.
Aug 8, 2007
1,585
102
64
Lancaster, PA
Jun 13, 2011
#7
  • Jun 13, 2011
  • #7
I did mine in 3-1/2 hours.. If you know where all of the bolts are that need to come out are it's not that bad..
 

Onefine88

Previously 89SSC18
10 Year Member
Aug 3, 2006
1,422
796
154
Jun 13, 2011
#8
  • Jun 13, 2011
  • #8
Yep, time for a heater core. Might as well change the A/C core while your in there too.
I've owned Foxes for more than 25 yrs now. I've gotten pretty quick at it as well. Ford could have made it a little easier for us.

Funny though,, I always have screws,nuts, bolts left over when I'm done. LOL

Good luck on your first time.
 
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alcougar1968

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Jun 11, 2011
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Jun 14, 2011
#9
  • Jun 14, 2011
  • #9
+1 on doing the ac evaporator at same time. As a mechanic any car that needs either heater core or evaporator I always try to get the customer to do both. Most cars now take over 8 hrs to do. the fox body heater box is easy in comparison. Any car it just makes sense to do them both while in there. even if your ac is not working but you plan on fixing it it's worth the few extra bucks.
 
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