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Vacuum Issues In AC & Heater

  • Thread starter Thread starter Sompin2do
  • Start date Start date Jul 15, 2006
S

Sompin2do

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Nov 30, 2004
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Jul 15, 2006
#1
  • Jul 15, 2006
  • #1
On my 90 GT I'm having issues with the blower direction switching by itself when I accellerate. It's going back and forth from vent to defog. How do I check for a vacuum leak? Everything under the dash is connected so maybe it's the cannister? Where is that located? I don't have much troubleshooting experience in this area so any help is appreciated.

Thanks
Mike
 

jrichker

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Jul 15, 2006
#2
  • Jul 15, 2006
  • #2
You are missing either the check valve in the vacuum system or have a missing vacuum canister or vacuum leak

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/

Diagram courtesy of Tmoss & Stang&2birds


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

http://www.veryuseful.com/mustang/tech/engine/images/fuel-alt-links-ign-ac.gif

http://www.veryuseful.com/mustang/tech/engine/images/88-91_5.0_EEC_Wiring_Diagram.gif
 

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  • mustangFoxFordVacuumDiagram.webp
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