Help!!! The Ac Has A Vent Problem It Blows Thru Defrost Then Floor Then Vent. Help!

stuartnh · #1 08-03-2005, 04:14 PM

I have a 2001 Windstar. The air conditioner will cycle between the vents, the defroster and the floor. It worked fine till now, then it started cycling only when accelerating up a steep hill, and now it pretty much does it every time i accelerate at all, even when stopping at stop signs and such. It will blow through the vent, which is normal, and then cycle to blowing through the defroster for maybe 10-20 seconds and then will cycle to the floor and finally back to the vent. As long as i'm just driving down the road on flat surface, it seems to work ok. I'm pretty sure it's some kind of vacuum problem, as i think everything is vacuum operated in the climate control. Anybody have any ideas or had this particular problem before?
Now it just goes to the defrost.

garync1 · #2 08-04-2005, 07:51 AM

Sounds like the motor that controls the air flow to the vents. I have to get back too you on that if someone does not bail me out... No not all the features of the climate control are vacuume controled if any on the 2001 Thats what I have as well My blend door went out so my AC did not work..Was blowing warm air out.. The blend door motor gears were worn a 56.00 or so fix, air works fine..Your climate control switch may not be working normal causeing it to run to various zones... Or a short something.. Ill check on it for you...

garync1 · #3 08-04-2005, 08:02 AM

Quote:

Originally Posted by garync1

Sounds like the motor that controls the air flow to the vents. I have to get back too you on that if someone does not bail me out... No not all the features of the climate control are vacuumcontroled if any on the 2001 Thats what I have as well My blend door went out so my AC did not work..Was blowing warm air out.. The blend door motor gears were worn a 56.00 or so fix, air works fine..Your climate control switch may not be working normal causeing it to run to various zones... Or a short something.. Ill check on it for you...

That part of the system may be vacuum related seeing that the book is only showing the blend door motor nothing on the vent system... ???I do see the chart for the climate controls which lead to the blend door.. But that is the heat and cool slides... HMMMMMMMMM....

stuartnh · #4 08-04-2005, 12:06 PM

The air is cold! Under the dash are vaccuum controlled units that change the direction of the air to either the vent, defrost or floor. The direction of the air is the problem. I think has lost vaccuum and is not enough to move them??? Could this be an EGR valve causing the loss of vaccuum?

busboy4 · #5 08-04-2005, 07:54 PM

Quote:

Originally Posted by stuartnh

The air is cold! Under the dash are vaccuum controlled units that change the direction of the air to either the vent, defrost or floor. The direction of the air is the problem. I think has lost vaccuum and is not enough to move them??? Could this be an EGR valve causing the loss of vaccuum?

Hi, EGR does not figure directly here. Your system should default to defrost in the absence of vacuum. Are you in a certain mode at a certain time? i.e. do you mostly go to defrost at idle? Normal flows at speed?

stuartnh · #6 08-04-2005, 10:55 PM

Acceleration earlier did matter but now the ac comes out of the defroster vents all of the time, no matter what. I removed the radio and center consol, checked for leaks and reseated the lines at the switch and at the vacuum motors I manually moved the vents at the motors with normal resistance. I followed the vacuum line as close to the firewall on the passenger’s side as I could (the blower motor prevents seeing the last few inches). I then checked the vacuum line at the motor for blockage & leaks, I see no blockage or leaks.
An article I found on-line mentioned it could be a bad canister check valve. I went to a Ford dealer today and they said they never sold any nor did any dealers close by us have any of these valves. The dealer did give me the part number though! Any ideas would be appreciated.

busboy4 · #7 08-05-2005, 08:21 PM

Hi
Sounds like you have looked pretty carefully. It still seems obvious to me that you are loosing vacuum as the vents should default to defrost (unless in 2001 ford started doing things totally differently). As to the check valve, unless it is leaking I agree with Ford. Take some time to look carefully at your vacuum lines as they leave the back of the intake manifold. On my '96 I found a hole worn in one of the semi-rigid tubes between the intake manifold and the vacuum tank, which on my van is located under the cowl behind the right side strut.
One other post I read said his problem turned out to be the control panel itself.

stuartnh · #8 08-05-2005, 10:55 PM

Thanks BusBoy4 for all your help. My 01 seems to be the same as yours. I have a few questions if you don't mind.
Can you reach the hose at the vacuum tank without taking too much apart behind the strut from under the hood or is this done under the dash (the tank end)?
I don't know the names of each part, when you say control valve, is this the selector switch that has max ac, defrost, heat, vent and the others on it and that's all vacuum controled?
Just so I am looking at the right item. How could I test it?
I am going to use my brothers vacuum pump, I plan on checking to see if the system holds presure by removing the line at the manifold, would this be a good idea? Should it hold presure? Maybe I could hear a leak with the motor and fan off.

busboy4 · #9 08-06-2005, 01:22 PM

[quote=stuartnh]Thanks BusBoy4 for all your help. My 01 seems to be the same as yours. I have a few questions if you don't mind.
Can you reach the hose at the vacuum tank without taking too much apart behind the strut from under the hood or is this done under the dash (the tank end)?
>>>The vacuum tank on my van is on the engine side of the firewall. I would suspect yours is there too. On my van I followed a Red semi-rigid appx. 1/8" diameter vacuum hose up to the check valve which was located just next to the vacuum tank. From the vacuum tank to the interior, the line was black.

I don't know the names of each part, when you say control valve, is this the selector switch that has max ac, defrost, heat, vent and the others on it and that's all vacuum controled?
>>>Yes. I read on this forum where a guy was having similar trouble and he changed the interior panel. He had a later model like yours.

Just so I am looking at the right item. How could I test it?
I am going to use my brothers vacuum pump, I plan on checking to see if the system holds presure by removing the line at the manifold, would this be a good idea? Should it hold presure? Maybe I could hear a leak with the motor and fan off.

>>> I think using a hand vacuum pump is a great plan. I used it to put vacuum on the system, and also test available vacuum. You should have around 13 "/hg vacuum at the vacuum block under the dash above the accelerator - the line from under the hood should have vacuum at that point with the engine running. On my van, that block was easily recognizable - the multi-colored lines from the individual vacuum motors all connected there. I was able to open that connection, and then using the attachments for my vacuum pump (specifically the needle nosed type) either pull a vacuum on a specific line, or measure available vacuum such as from the engine. If you can pull a vacuum at that point on the line which runs from the engine (the one you followed before) it should hold. That would test the line from there to the tank, the tank itself and the check valve. If it holds, your problem is between the engine and the tank, or between the connector block and (or at) the panel switch unit.

Let us know what you find
Happy hunting. let us know what you find

stuartnh · #10 08-06-2005, 02:20 PM

Thanks for all the help again and I will let you know what my results are, it may take me into the end of next week. I need to get the pump from my brother and then have the time and the car (its the wifes) so that means it REALLY needs to be fixed...
Thanks,
Stu

stuartnh · #11 08-18-2005, 12:15 PM

Busboy4 I need your help!

I checked under the dash at the block on the drivers side and I have a black and orange line that run behind the glove box and blower motor back to the firewall where I can't see them anymore. On the engine side at the firewall I see an orange hose going to the back passerger-side of the motor.

With the van running I have no vacuum at the block other than maybe 1.5 on the black line. With the car off only the orange line pumps up at the block and holds vacuum. I can pump the motors up and they do move at 13 as you said they would on the half of the connector.

I think my problem is between the engine and the block under the dash but it's hard to make sense of it?

What items are between these two points? How should they read?
I was hoping to measure some vacuum, maybe its the engine intake leak? I tried to get a line on the engine but I did not have a big enough connector at the engine. I am going to find something to use to see what the vacuum is at the engine real soon.

busboy4 · #12 08-18-2005, 07:52 PM

Hey Stuart
check the vacuum motor under the glove box -that should be the recirc vs. outside air vacuum motor. On my '96 that motor gets the orange line. That way you will at least know which line is which. I think you will find the orange held because it simply moved the vacuum motor and then held it. Ya know?

Again if they didnt change things much between our model years - the vacuum is pulled at the back of the intake manifold, runs up to the right rear of the engine compartment to the vacuum check valve, then to the vacuum reservoir(all on engine side of the firewall) then straight to the vacuum block you located. I am going to go out on a limb and bet your leak is on the engine side as there are more places for chafing to take place and wear a hole in the vacuum line.
Regarding your orange line in the engine area: on my van, a red line runs up to the vacuum check valve, and from then on it is black down to the vacuum block. On my machine, the red line had the hole due to chafing on the A/c suction line.

Good luck and keep us up to date.

stuartnh · #13 08-19-2005, 09:13 AM

When I drop open the glove box all I see is the blower motor mounted to the duct work that runs side to side under the dash and the firewall behind it all, these lines go up behind the duct work. I was thinking about using my garage air compresser set down to about 5 lbs. of presure and hooking it up to the vacuum line at the motor and see if things work correctly or not or if I can then hear a leak. With the hand pump if I have a leak I can't pump it fast enough or quiet enough to find a leak. The next step would be to test to see if the motor has any vacuum, that should be easy enough. I have been sick for the last week and still don't feel real well that's what the delay has been!
What do you think of those ideas?

12Ounce · #14 08-19-2005, 09:46 AM

I'm gonna jump in to say that putting even just 5 psi on devices made for vacuum would make me nervous. It may be OK, but I would want to hear someone say they've done it and it's not going to damage anything.

Another good source for vacuum is to hook a hose up to another idling vehicle if you have one available. ... or if you can hook up to the Shop Vac, that may work.

busboy4 · #15 08-19-2005, 06:38 PM

Hey Stuart
the vacuum motor I am talking about is visible from under the dash on the passenger side. Look up from the floor level. I hope you will see a vacuum motor - I doubt they have changed things much. This I hope will solve for you which line is which.

I think I too would be careful about using positive pressure to find your leak.

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