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DD HVAC vacuum question

tarafied1

tarafied1

Well-Known Member
Not really Mustang related but could translate. I have a 2000 Expedition, the AC blows out the defrost rather than panel. Everything I find on the web says vacuum leak but I cannot find one. I did find the actuator for the panel. I unplugged the vacuum line and measured about 4 inHG. If I use my vacuum pump, it takes about 10in HG to overcome the spring in the actuator and open the door all the way.
My question: how much should I have?
 
Not sure on the amount you should have but that is the standard feature in Fords.....fail to defroster when no vac. is present. Older vehicles had a hard plastic white main line thru the firewall, just off center to the passenger side. I have seen them fail like yours yet check close to good due to the line being moved a bit. I would bet there is a leak in the main feed into the dash.

Found this too... http://www.ford-trucks.com/forums/91945 ... blems.html
 
A lot more than 4 at idle. It should be darn close to the engine vac at idle, and should hold there even off idle (unless the vac canister is bad, or there is a vac leak). My '68 runs full engine vac - I use those lines to hook up the vac guage.
 
that's what I figured, it should be close to engine vacuum. The link Pete gave me had another link to a repair on the EATC, I am going to check that. My Expedition is a Eddie Bauer and has the EATC. The vacuum I measured was coming from that unit. I will check vacuum prior to the EATC and verify that it is probably higher.
 
I checked the vacuum going into the EATC and was 20 so I know that it's something there. The link shows some O rings that leak so I will try that to see if it fixes it. Thanks for your input and for that link Pete
 
No problem....glad I found something that helps.......did you like the nekked girls in it too.....
 
"AzPete" said:
No problem....glad I found something that helps.......did you like the nekked girls in it too.....
Click to expand...
I must have been concentrating on the text too much, I didn't notice nekked girls...
 
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