Thread: A/C/Heat air blows ONLY from defrost vents and floor

I've seen a couple post about this over the years.

I changed the vacuum manifold that's under the dash by the blower motor.
And I just tested that line that runs on top of the blower to inside the car today and still only blows from defrost vents and floor...

Anything else I can check?

This is very helpful
http://www.justanswer.com/pontiac/4g...nts-floor.html

But one. I have never been able to find the vacuum reservoir and two I'm pretty sure I don't have a Vacuum T on that plastic line that goes down the passenger side fender well by the battery. The same line that hooks to the top of the blower.

Thanks
Steven

I remember reading about a rod that runs by the blend door actuator, sometimes gets disconnected, might be worth a look.

seen the climate control take a dump and cause this also, seems like you checked it all so far.

Originally Posted by 99GT2dr

I remember reading about a rod that runs by the blend door actuator, sometimes gets disconnected, might be worth a look.

Where's that exactly, on the passenger side?

Originally Posted by ScottyBDoggs

seen the climate control take a dump and cause this also, seems like you checked it all so far.

Well I changed it out for a red one many many years ago but I think it was still giving problems when I had my green one. It seems to function fine though.

You say you tested the vac line coming in. Did it have vacuum?

If no.. then here's the pic of that res, it's the black ball

Originally Posted by Ridin ON Chrome

Where's that exactly, on the passenger side?

Drivers side. Was on my car, imagine its the same on yours. There's a bracket it clips in to. Mine popped out of the bracket and wouldn't move the door. Just clipped it back on, fine since.

some cars dont have that vac ball. the vac line off the sc runs right into the cab of the car.

if you have a T under the fuse box, you have that ball for sure.

Originally Posted by BillBoost37

You say you tested the vac line coming in. Did it have vacuum?

If no.. then here's the pic of that res, it's the black ball

Yeah, do have vacuum. Went under the dash while the car was running. Pulled that line off and it's sucking..lol

Could that box that line plugs into be bad?

Originally Posted by bandook

Drivers side. Was on my car, imagine its the same on yours. There's a bracket it clips in to. Mine popped out of the bracket and wouldn't move the door. Just clipped it back on, fine since.

Need to check that next. Is that up under the dash?

Originally Posted by ScottyBDoggs

some cars dont have that vac ball. the vac line off the sc runs right into the cab of the car.

if you have a T under the fuse box, you have that ball for sure.

I really don't think I have one, I never noticed it when I did my I/C install..

There is a rubber fitting that connects the two hard plastic lines. One end is the one that comes off the blower, then other is was seem to go down the fender wall by the battery into a wire loom with a bunch of wires that go into the firewall. Which is the same plastic line I disconnected under the dash.

that box under the dash could be the issue. they sell new for like 18 bucks iirc on ebay.


follow this thread to open up the dash then watch the round vac pups in the diagram in this thread for movement when you change the air flow direction.

http://www.grandprixforums.net/threa...or-Replacement

Originally Posted by ScottyBDoggs

that box under the dash could be the issue. they sell new for like 18 bucks iirc on ebay.


follow this thread to open up the dash then watch the round vac pups in the diagram in this thread for movement when you change the air flow direction.

http://www.grandprixforums.net/threa...or-Replacement

Interesting. Wonder if I could check them so some how.

Will these work?
Same thing for either side right?
http://www.amazon.com/ACDelco-15-736...words=15920864

thats a blend door actuator. those only control hot or cold air, or the mix of both. nothing to do with the direction the air flows.

those round pumps are when changed the direction. take a look at them. the pass side one is east to see, take the glove box door off. but theres the other one too on the d/s.


side note thats damn cheap. most of the time they run 50 ish.

Thats the little thing at the bottom of the pic?


What are they supposed to do?


btw. Thanks for all your help man. I really appreciate it.

the thin line at the top is the vac line from that box under the dash. ( its yellow in real life) the linkage arm you see is what moves the air flow direction.

if those arms dont go up and down when you tell the cc to change, (CAR RUNNING) that box could be bad. if they move make sure the linkage arms are not broken. they break on their own some times.

Boy that thing was a pita to check..

Laid upside down and fooled with the HVAC mode and the little plastic thing went it up and down..

But it looked the top of it was broken and hitting something. But now looking at that pic. That arm it attached too is not connected so that's why the air flow changing.
This was on the drivers side..Didn't check the passenger side.

Wonder what the part number is on those things.

What's that thing called btw?

it seems its best to pull the dash out for that repair. iirc the same thing happened to GMRbadass's 98 gtp. iirc they were able to fix it without taking the dash out, but iirc it was a glue it back together, not parts replaced.

jay, bill and greg were all there for that fix, maybe one will chime in.

Originally Posted by ScottyDoggs

it seems its best to pull the dash out for that repair. iirc the same thing happened to GMRbadass's 98 gtp. iirc they were able to fix it without taking the dash out, but iirc it was a glue it back together, not parts replaced.

jay, bill and greg were all there for that fix, maybe one will chime in.

Oh hell no!! hahaah.. You mean dash as in the whole the whole thing that does all way to the windshield?

I could use some super glue, but yeah it would be a ***** trying to get it up there.

You don't remove the dash to fix it.. geez

Originally Posted by BillBoost37

You don't remove the dash to fix it.. geez

tell him how to fix that damn little plastic part you guys fixed up once upon a time lol

Originally Posted by ScottyDoggs

tell him how to fix that damn little plastic part you guys fixed up once upon a time lol

Yeah, tell me.. hahahaha or whats the part number so I can buy a new one..lol