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AC doesnt fully work

1405 Views 12 Replies 6 Participants Last post by  CBG
my ac will kick on, but will only come out the defrost vents, any ideas?
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i am also having a similer problem in when the selector is on regular a/c it only blows cold air out in spirts, but works fine on max a/c
Predator is having the same problem...there is a post about it somewhere.

I suggested a vacuum problem, but he says he checked them all. I'm not sure if he ever got it fixed or not.
I am having the same problems. Changed the blower resistor and nothing changed. Fuses are all ok and I know that it must be the vacuum. We are all looking for a solution; please help us FastCougar owners and contributors.
Having the exact same problem here, anyone has a clue please post!

It actually used to start off in defrost and then slowly move to other settings, now it just stays in defrost vent setting
Ok solved mine. It was a rubbed/abbraded/burnt/melted vaccum line in the engine compartment that passes through the firewall. It is a grey line connected to a black line ( the black line passes the firewall)

Diagnosis: Removed glove box and then removed vacuum line comming in from engine ( see photo), placing thumb over end (with engine running) felt no vacuum, the let me know that it was in the engine compartment.

In the engine compartment- I traced the vacuum lines, the grey line ( center line on engine, on top, near firewall) comes off a "T" and provides the vacuum for the vacuum actuators in the cabin that move from defrost to other positions. . Upon inspection with a flashlight, I could see a darkened spot on the line about 4-5 inches down from the junction, that appeared to be melted, leaking etc.

Remedy: I cut the piece off, went to AutoZone, got some 1/8 " HVAC tubing and some conectors. I used that to patch the line. ( Word of caution, there was virtually no slack in the line, where you cut is where you will be mending, not a lot of space behind engine to force on a connector)

Result: Everything works fine, I can switch from defrost to panel and it works.

I have attached some images for reference.


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Nice find and how-to!!

I will work on this tomorrow, hopefully it solves the problem I've been having. I'll post back on any updates.

Thank you!
yes, thats a great how-to, im going to tackle mine tonight
well, i followed the directions and it worked, thank you soo much :-D
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