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Help Vaccum Leak

  • Thread starter Thread starter DStang99
  • Start date Start date Jun 14, 2009

DStang99

Member
May 11, 2009
46
1
7
Florida
Jun 14, 2009
#1
  • Jun 14, 2009
  • #1
Hello


I have a 1999 GT stang For some reason the ac will not blow air out the main air vents just the feet vent and the defroster. so im guessing it a Vacuum leak but i cant seem to fine where it could be. It must be in the engine compartment somewhere because stopped working after i change the spark plugs
Any help Would be appreciated




THanks:SNSign:
 

AdRock

Member
Nov 13, 2003
521
1
19
South Texas
Jun 14, 2009
#2
  • Jun 14, 2009
  • #2


On the intake plenum there is the vacuum fitting that is between the TB and the IAC. There sould be a rubber fitting on it with 2 or 3 small plastic vacuum lines coming out of it. These are the lines that feed vacuum to the AC controls. The small plastic lines can get brittle and crack over time. Check these and see what you find.
 

DStang99

Member
May 11, 2009
46
1
7
Florida
Jun 16, 2009
#3
  • Jun 16, 2009
  • #3
AdRock said:


On the intake plenum there is the vacuum fitting that is between the TB and the IAC. There sould be a rubber fitting on it with 2 or 3 small plastic vacuum lines coming out of it. These are the lines that feed vacuum to the AC controls. The small plastic lines can get brittle and crack over time. Check these and see what you find.
Click to expand...

Thanks for the help
I checked the TB seems fine is
there any other line i should check????
 

R.J.

Member
Aug 20, 2003
813
0
16
Warwick, Rhode Island
Jun 18, 2009
#4
  • Jun 18, 2009
  • #4
You need to check more than the TB. Have you have found the rubber fitting previously mentioned? You have to follow the two red, hard plastic vac lines that come out of it. They will follow the pass side cam cover and then connect to rubber lines that go into the fire wall. Check them from the TB to the firewall.
 
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