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Ac Coming Out Defrost Vent

  • Thread starter Thread starter Themacdaddyj
  • Start date Start date Mar 29, 2016
  • Tags Tags
    air defrost leak sn95 vacuum vent
T

Themacdaddyj

Member
Mar 23, 2016
5
2
13
Mar 29, 2016
#1
  • Mar 29, 2016
  • #1
Whenever i turn my air on, it only works coming out of the defrost vent regardless of where it's set. I've read up and found a common source to be a vacuum leak.

My mechanic looked at it this morning and said that if it was a vacuum leak he would be able to hear it and the engine would run rough.

Instead he thinks the problem is a switch in the dash.

Thoughts?
 

Noobz347

Stangnet Facilities Maint Tech... Er... Janitor
Admin Dude
Jan 4, 1985
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Box behind Walmart
Mar 29, 2016
#2
  • Mar 29, 2016
  • #2
Thoughts... Hmmmm....

You need a new mechanic. The problem "IS" a broken vacuum line, and it "IS" either behind the dash on the passenger side or up against the firewall on the passenger side.

This 'default' position to the defroster vents is as old as the very first Fox.

Your mechanic knows nothing at all about Mustangs.
 
T

Themacdaddyj

Member
Mar 23, 2016
5
2
13
Apr 15, 2016
#3
  • Apr 15, 2016
  • #3
That's what I figured. I was thinking about replacing all of the vacuum lines just to save myself the hassle of fixing another leak down the road. The funny thing is a Fox rolled up to see him right as I was leaving. I hope it's not in the line in the dash because I was hoping to avoid changing that line. But I'll have to see.
 

wolfheads

Member
Jul 17, 2018
39
1
18
Florida
Aug 17, 2018
#4
  • Aug 17, 2018
  • #4
My 94 gt was doing the same thing. My mechanic found it was a vacuum line. Works in all positions now.
 
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