Defroster blower

[tallbump]

So, when I turn on the defroster (the front windshield one), it sounds like it is blowing, but nothing comes up out of the top of the dash. If you put it on heat or vent, it comes out of the front vents. When on defrost, the passenger side clears but the driver's doesn't (nice this time of year in this part of the country) although you can't feel anything on either side.
Any ideas?

[LordDurock]

check the for vacume leaks.......some one else we have to descrive this as i have not freaking clue after vac leaks................

[tallbump]

Ummm...no idea what you mean:dunno:

[LordDurock]

the heater controls use a the engine vacuum to move the devertor flaps (the flap that route air to the def vents or the forward vents etc)
if one section of the contrails has a leak the flap wont move.

[turbokinetic]

Usually; with NO vacuum, the air will exit the defroster vents. Vacuum is normally required to make the air come out the dash and floor vents.
I would say there is a physical obstruction in the mechanism either causing the defrost mode door to be jammed; or there is a piece of insulation broken free that is blocking the air flow.
The "mode" lever that selects "Max Norm BiLev Vent Heat Def" is actually a valve. It opens and closes vacuum signals to diaphragm actuators in the dash. These move the mode doors in the air ducting and direct the air to the vent you selected.
As LordDurock explained, any leakage or blockage in the vacuum system will play havoc with it!
When you select Def mode, does the air come out any of the vents (floor or dash) or is it closed off completely (no air from any outlet)?

[tallbump]

When you select Def mode, does the air come out any of the vents (floor or dash) or is it closed off completely (no air from any outlet)?

It still comes out of the dash vents when i switch to defrost.
Like I said, the weirdest thing is that you can't feel air coming out of either side defroster, but the passenger side clears MUCH faster then the driver's side.

[turbokinetic]

Did it happen all at once? If so I bet the Defrost mode door mechanism is stuck.

Could it have happened after some other maintenance or service? Could some vacuum tubing have been misrouted?

Could some foreign object fell down the Defroster vent and jam the mechanism?

Just a few thoughts!

[BignastyGS]

The reason that is,because thats the side that the blower motor is on for one thing,but also the heater core (which is like a small radiator) is also on that side of the car behind the dash. As the motor warms the antifreeze it flows through the heater core and then the air from the defroster fan pushes it out into the vents,thus the passenger side of the windshield will defrost faster.

[tallbump]

Hmmm...no service since I have had the car except rear brake work.
This is the first winter so it has been happening since winter started, i have no idea how long before we owned ti it stopped working.
How do I get a look at everything to see what the problem is?

[turbokinetic]

I tried to look at a diagram of this system but couldn't find one.
On a Century, you can see some of the HVAC controls by removing the glove compertment. Not sure which parts are visible due to not having to work on that. Only problem I have had is a broken blend door cable (warm cool) that was fixed with a lawnmower throttle clip.
On the Olds I have never done a dash work on that car. Probably some others here can tell you exactly how to look at the actuators.
Best luck!

[tallbump]

No new ideas?
I had this problem big time yesterday morning trying to get the kids to school and get to work.
:dunno:

[LordDurock]

tell then my i recomend a small 12 heater that plugs into the ciigret lighter

[85_Ciera_Rebuild]

No new ideas?

Did you take apart your glove box...or look behind it for a vacuum switch/pot?

Otherwise, have you tried sunbathing in the winter (http://www.cabanaslosandes.com/740a.jpg) in Cabañas Los Andes, Chile?

[turbokinetic]

]tried sunbathing in the winter[/U][/URL] in Cabañas Los Andes, Chile?

That looks COLD!!!!! I want to place a towel over her just looking at that picture!!!



Hey I looked at my 84 Century's HVAC system yesterday and figured out the following:

A- There is one dual-acting actuator that selects between floor, panel, or bi-level. It is visible with the glove box out. No vacuun either port = bi-level, one port directs air to panel vents, other port directs air to floor vents.

B- There is one single-acting actuator that selects between defrost, or normal operation. No vacuum, door diverts 100% of the air to Defrost outlets at base of windshield. Vacuum applied, air is allowed to continue to the floor/ panel/ bi-level ducting.
This actuator is up high in the dash and I could just barely feel it reaching back in the dash. I'm very flexible and someone else might not be able to reach it. I could barely touch it.

C- there is a single-acting actuator above the ECM bracket that selects recirc or fresh air. No vacuum = fresh air, vacuum applied = recirc mode.

D-There are 2 vacuum tubes going to engine compartment. Pink one is vacuum source, and grey one (IF USED) is heating water shutoff valve.

If air still comes out the dash vents when you switch to Defrost, either the actuator "B" is mechanically jammed, or the vacuum circuit is holding vacuum on it. The small rubber vacuum hose could be pinched (trapping vacuum in the actuator) or maybe the HVAC control head is bad. Do you have a mechanical air conditioner control or the "electronic climate control" system?

[Tuddi]

Sunbathing in the winter ... laying on a plastic chair... that's not how it's done!

Doing it in Iceland is tricky, since there is no sun getting over the horizon. But taking a hot bath in natural thermal waters, requires frequent cooling down in either snow or getting into ice cold water in a river not completely frozen stiff.

That's what we used to do at my mother's house in Iceland (http://www.flashearth.com/?lat=64.115041&lon=-21.834046&z=17.7&r=0&src=ggl) that is located in the middle of the capital city Reykjavik, but still uniquely away from everyone else (zoom out to see how it is placed).

[tallbump]

I have the mechanical controls.
Haven't pulled the glove box yet cause wouldn't know what to look for, and It's been like less than 20 degrees lately and my garage isn't heated.
Didn't happen to snap any pics back there did you?

[LordDurock]

I have the mechanical controls.
Haven't pulled the glove box yet cause wouldn't know what to look for, and It's been like less than 20 degrees lately and my garage isn't heated.
Didn't happen to snap any pics back there did you?

put on a sweat shirt and sit in side your car and remove all the screws with a 7mm shockit. it will be every warm after a while ;)

[tallbump]

Hmmm....yep, that would work.

Now, I just need to know what I am looking at....
I need to get a FSM off Ebay

[LordDurock]

well if you take the glove bok out it easy you figure it out. then you will see a red clip that hold the hot cold selector wire sheath in place. and nexted to that should be a round thing that looks like a speaker but its not. after that i dont know

[turbokinetic]

Sorry I didn't get pictures. I was waiting on my repaired engine (rod bearings) to warm up and just thought about feeling around for that actuator. Didn't think to take pictures. Might get a chance to do that later. Hope you can figure out this problem before then.

I know it is dangerous having no defrost. My 1972 Nova (with 36 years old A/C controls) will sometimes randomly disengage the A/C compressor and you will have to "wiggle" the selector to get it back on. When this happens in cold wether in Defrost mode, the windsheild INSTANTLY foggs up as the moisture from the evaporator coil blows out the vents. It is dangerous but if you wigggle the control and the compressor kicks back on, the fog disappears as quick as it appeared. Scarey, though.

David

[tallbump]

Wow, instant fog would be scary.
This issue is really getting annoying.
I'll try taking the glove box out, maybe I'll get lucky and something will be obviously wrong looking.

[tallbump]

So, how do I get in there to take a look?
It is rally getting bad, not safe at all.

[tallbump]

BUMP......

Any idea of how to get the glove box out. Or does that panel above the glove box come off?
This is really getting a safety issue for my family.

[Tuddi]

This here is a "must" product to treat your windows with. No matter if your blower/heater works or not.

http://www.amazon.com/Rain-X-Anti-Fog-3-5-oz/dp/B0002JN26I/ref=pd_sim_auto_img_1

... and while you are at it, you should also buy Rain-X for exterior treatment of your glass surfaces.

[85_Ciera_Rebuild]

Any idea of how to get the glove box out.


I don't know the specifics...but it use to be:

1. Take glove box "door" off first....use to be machine or sheet metal screws there when you open the door you should see them.

2. Paper/plastic box use to have screws/clips/etc that held it in place...

[tallbump]

I'll have to take a look for teh screws.

I have used the rain X stuff for the fog, still not helping.
I haven;t put the regular stuff on the outside.
Actually, i was just thinking about that the other day.

[tallbump]

Okay, i took a look.
I could not find any screws to take out to allow me to remove the glove box.
Didn't help that both of my flashlights died out on me.
Any one got any pics or give a good description on where to look.
I charged both flashlights so it should be easier this time.

[85_Ciera_Rebuild]

Any one got any pics

Open your glove box, and take a pic looking down at hinge...and post it

PS: Also, on bottom side of dash, take a pic looking up at hinge area.

[tallbump]

Will do