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Ac/heater Vacuum Lines

  • Thread starter Thread starter 6ScubA9
  • Start date Start date Oct 9, 2013

6ScubA9

Member
Oct 9, 2013
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1
9
Oct 9, 2013
#1
  • Oct 9, 2013
  • #1
Hello all! Brief intro: I bought a 92 Mustgang GT (pics soon) about a month ago. Good price has some upgrades but definitely a project car. The a/c has all the lines ripped out (for more hp i assume). The air only blows out of the defroster vent and from the floor (not really sure if it's from floor vents or otherwise). The defroster blows warm air but not out of the floor. I've read that it's the vacuum lines but there are a lot of them and if it's like everything else on the car it's missing some. As far as anything i've found goes on vacuum lines is to the vacuum tree, no help after that. So if someone could give me a quick rundown that would be awesome! Here's some pics with the questions i have. Thanks!

This one is on the passenger side and the hose running from the top middle of the picture comes off the split where the a/c line comes from the vacuum tree. How many hoses should come in, what are they, where do they come from? As you can see one hose is routed on two nipples, closing them off i guess? is there something that should go to this?



and here is the bottom (best angle i could get)



here are the hoses under passenger dash. how many hoses should go in/out, where do they come from/go?
 

jrichker

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Oct 9, 2013
#2
  • Oct 9, 2013
  • #2
Diagrams courtesy of Tmoss & Stang&2birds

Under the Dash HVAC diagram



Under the hood vacuum diagram



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif


Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
 

6ScubA9

Member
Oct 9, 2013
36
1
9
Oct 9, 2013
#3
  • Oct 9, 2013
  • #3
T
jrichker said:
Diagrams courtesy of Tmoss & Stang&2birds

Under the Dash HVAC diagram


Under the hood vacuum diagram



See the following website for some help from Tmoss (diagram designer) & Stang&2Birds (website host) for help on 88-95 wiring http://www.veryuseful.com/mustang/tech/engine/ Everyone should bookmark this site.

Complete computer, actuator & sensor wiring diagram for 91-93 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/91-93_5.0_EEC_Wiring_Diagram.gif

Complete computer, actuator & sensor wiring diagram for 88-91 Mass Air Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif

Ignition switch wiring
http://www.veryuseful.com/mustang/tech/engine/images/IgnitionSwitchWiring.gif

Fuel, alternator, A/C and ignition wiring
http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif


Vacuum diagram 89-93 Mustangs
http://www.veryuseful.com/mustang/tech/engine/images/mustangFoxFordVacuumDiagram.jpg

HVAC vacuum diagram
http://www.veryuseful.com/mustang/tech/engine/images/Mustang_AC_heat_vacuum_controls.gif

TFI module differences & pin out
http://www.veryuseful.com/mustang/tech/engine/images/TFI_5.0_comparison.gif

Fuse box layout
http://www.veryuseful.com/mustang/tech/engine/images/MustangFuseBox.gif

87-92 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang87-92 PowerWindowWiring.gif

93 power window wiring
http://www.veryuseful.com/mustang/tech/engine/images/mustang93PowerWindows.gif
Click to expand...
Thanks! That's a lot of info to go through and definitely appreciate it!! I was hoping for "looks like you're missing (applicable hose)" or something to the effect. The diagrams are confusing and was hoping for color real life pics.
 

6ScubA9

Member
Oct 9, 2013
36
1
9
Oct 9, 2013
#4
  • Oct 9, 2013
  • #4
Ah man. The pics didn't post. I'll try again to get them up.
 
B

Bee

New Member
Dec 7, 2019
15
1
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Florida
Aug 29, 2024
#5
  • Aug 29, 2024
  • #5
6ScubA9 said:
T

Thanks! That's a lot of info to go through and definitely appreciate it!! I was hoping for "looks like you're missing (applicable hose)" or something to the effect. The diagrams are confusing and was hoping for color real life pics.
Click to expand...
Are these diagrams accurate for the SN95 too, or just the Fox platform? If they're different, do you know how? Can you tell me where the vacuum line for the A/C controls in in the engine bay of 4.6L SN95? Mine is stuck on defrost.
 

General karthief

wonder how much it would cost to ship you a pair
5 Year Member
Aug 25, 2016
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polk county florida
Aug 29, 2024
#6
  • Aug 29, 2024
  • #6
Bee said:
Are these diagrams accurate for the SN95 too, or just the Fox platform? If they're different, do you know how? Can you tell me where the vacuum line for the A/C controls in in the engine bay of 4.6L SN95? Mine is stuck on defrost.
Click to expand...
Basically 87-93, the 94-5 models may differ some. You're gonna have to move to the forum that matches the year mustang you're play' with. The 4.6 is a totally different animal, no worries, not vicious at all.
I will add that it's likely the main vac line that supplies the controls is broken and prolly runs along the top of the fkrewall.
 
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