Ac Vents!!!

[SpoolinGN]

I remember a post on here not to far back that refered to my problem but can't find it.

When i turn my A/C or heat on it only comes from the floor and some for the defrosters. When could make it not come for the dash vents?

Thanks for all the help

Scott

 

[Pats-GN]

I've had this problem on and off for a year and havent found the answer. You might try the vaccum switch behind the climate control (didnt fix mine), also check the bladders under the dash, I think thats my problem because the only time my vents work is on bi-level.

pat

 

[FRANKIEz28]

Check the plastic lines in the engine bay. They run along the along the blower and a/c acumilater and behind the coil pack. Sometimes they crack due to age.
Mine cracked from moving them around while fixing stuff under there.
One time I had one of the plastic lines find itself under the coil pack when I tightend it down

Good Luck
FRANKIEz

 

[SpoolinGN]

Same here, but after they broke i put a vaccum line in between the brake.

I noticed that one of the lines goes into a T fitting kindof. but gets fat to one end, but while i was working on the car on of the fittings broke, so i put a new t fitting in but blocked of the line that gets a check valve so it kind of works the same way.

could that be the problem?

 

[SpoolinGN]

Any other ideas???

 

[turbo nasty]

Welcome to the g body curse. We have a little G body club here and all of the boys with cars from 82 -87 have the same problem. There is an Oring in the a/c climate module that gets flat and does not allow the vac signal to do its thing. On mine I have to put it to bi level to keep it acting right or sometimes it will stick like you discribed ..then slam you here it open. My bud that told me about the o-ring is an a/c guru and there is also some type of door that will help also if it is greased. I have to get mine fixed a/c stopped working so probably going with the 134 conv. Ford works better with the 134a due to their 5 piston comp. vs. GM 3

 

[GNSteve]

Spoolin'

I had this problem about a year ago. Check ALL of your 1 way vacuum check-valves under the hood. If any of them are bad (like mine were) they'll allow the vacuum to escape, causing the problem you described. My problem occurred under boost, when my AC would suddenly disappear, then reappear by the floor and the top of the dash.
I would check all vacuum lines, the vacuum "storage ball" by the drivers side fender, the vacuum dist. block, and all the check valves. Better yet, change out all the valves just to be safe. They should be available at any parts store. Good luck.


Steve

 

[Pats-GN]

Hey Spoolin,
Do your vents work on Bi-Level? If they do, this would lead me to believe its something under the dash, bladder, vaccum switch, line etc. Under the hood, check the hard lines, check valves. Also check the larger black valve near the coilpack that splits off to the EGR and towards the cruise. If its bad it will affect the vents. Let us know if you find anything.

pat

 

[salvageV6]

You should get vacuum to the blue, red, and yellow vacuum hoses off the vent control unit when the system is set to MAX A/C.

Feed line vacuum from the car is on the purple hose.

Follow those hoses to the bidirectional upper lower door controllers they may be stuck in the wrong positions.