2006 Legacy hot air on driver side, cold air on passenger side.

[Pinegrovesubaru]

2006 Legacy 2006 heater works great on the drivers side, but only blows cold air on the passenger side. The same situation happens in the defrost mode (hot air out of the left vent, cold air out of the right vent). The quantity of air varies with the fan speed, but the air is dead cold on the passenger side.
I looked under the dash and behind the glove compartment and found nothing.
I removed the center counsel to get a better look at everything.
The motor that moves the damper between vent, heat, and defrost is working properly.
The recirculate/fresh air motor and damper are working properly.
The linkage for the cold to warm adjuster is working properly.
I couldn't look into the air ducts to see the heater coil but I tried.
Having everything apart confirms the left duct is hot, the left-middle duct is warm, the right-middle duct is cool, and the right duct is cold.
I can't imagine the right side of the coil is blocked and the left side is open, but that is how it is acting.
Any suggestions as to how to get to the hot water coil to inspect it?
What boggles my mind is that the quantity of the air is the same all the way across the four ducts, but the air goes from warm on the left to dead cold on the right.
Thank you for any ideas that you have.

[New GT]

I just checked on alldata and it looks like there is an actuator for the passengers side air mix. It most likely is not operating or it has become disconnected.

[New GT]

http://www.motoralldata.com/alldata/MOTOR~V141275062~C42416~R0~OB0~P4R0H~N/0/115013665/117253666/117253857/117253859/34853741/34865608/34866121/120347129

[Pinegrovesubaru]

This is what I was looking for yesterday.
All the linkages I could see moved when I adjusted the controls.
Could this actuator be inside where it can't be seen?
You said you checked on "alldata". I am not familiar with this. Could you tell me about this?

[New GT]

The actuator should be like a little motor, that is on the right side of the heater/ac box. It would have a small wie harness going to it. Alldata is information that the auto industry uses for diagnosis and repair of vehicles. It is a pay to play service.

[Pinegrovesubaru]

The actuator should be like a little motor, that is on the right side of the heater/ac box. It would have a small wie harness going to it. Alldata is information that the auto industry uses for diagnosis and repair of vehicles. It is a pay to play service.

On the right side is the actuator that moves to change the air flow from vent/floor/defrost. It is working properly, moves between every station. The air flow is redirected properly.
On the left side is the manually operated actuator that moves the damper to make the air warm to cold. It moves properly too. The shaft goes from the left side and out through the right side of the duct. I can see the shaft on the right side turn when the left side turns so I'm sure the shaft is not broken. But is it possible that the damper broke so only the left side of the damper is moving on the shaft and the right side damper is always in the cold position? I tride to see this but I couldn't move the duct work enough to get my mirror inot the correct position to see into the damper.

How much does Alldata cost? Would it be worth it for a DIY'r maintaining five vehicles to pay for?

[New GT]

From what I can tell there are seperate air temp actuators from drivers side to passenger side.

[New GT]

I will try to post the pics again, but I would look at them ASAP.

[New GT]

http://www.motoralldata.com/alldata/MOTOR~V141280273~C42416~R0~OB0~P4R0H~N/0/115013665/117253666/117253857/117253859/34853741/34865608/34866121/120347129

[Pinegrovesubaru]

My car does not have this actuator.
I'm guessing that this drawing represents a car that has dual climate control (which mine does not).
So I'm back to thinking that the damper inside the ductwork that regulates the fresh air from the heated air has a problem.
Your thoughts?

[New GT]

Does it have auto air?

[Pinegrovesubaru]

No, it does not have auto air.

[New GT]

Then I have no idea what is going on. I wouldnt think that the right and left would have a different temp blend door without the actuators or auto air. Can you post a pic of that area of the heater box (the passenger side)?

[Dookie]

I copy this from the service manual, try checking these off and see if you can find the problem.


26.General Diagnostic Table





A: INSPECTION





Symptom Repair order


Blower motor - Does not run.

fuse
Blower motor relay
Wiring harness
Blower motor
Blower motor register (Manual A/C model)
Blower switch

Compressor - Does not run.
Refrigerant
Fuse
Air conditioning relay
Wiring harness
Magnet clutch
Compressor
Pressure switch
A/C switch
Blower switch



Condenser fan - Does not run.

Fuse
Sub fan relay
Wiring harness



Cold air not emitted.

Refrigerant
V-belt
Magnet clutch
Compressor
Pressure switch
Blower fan relay, blower motor
A/C switch
Blower switch
Wiring harness
Heater duct
Heater vent duct
Control unit
Expansion valve
Evaporator
Air mix actuator (Auto A/C), Temperature adjustment cable
(Manual A/C)

Warm air not emitted.

Engine coolant
Aspirator hose
Blower switch
Air mix actuator (Auto A/C), Temperature adjustment cable
(Manual A/C)
Heater core

[Pinegrovesubaru]

I checked all of these except for the 'aspirator hose'. I don't know what this is. Can anyone explain this to me?
Two other ideas I have. Could Bar's Leak and Subaru 'Blue Goo' antifreeze conditioner team up to clog the end of the coil, allowing the hot water to pass through the coil at the front (driver side) of the coil but allowing no flow at the rear (passenger side) of the coil?
How about air being trapped in the coil, not allowing any flow at that end of the coil.
I bled the air out of the system by running the engine at 3000 rpm for five minutes.

[New GT]

Did you put bars leak in your cooling system? I cant see where one side of the heater core would be colder than the other, as I believe it is a flow through design and not seperate from side to side.

[Pinegrovesubaru]

I copy this from the service manual, try checking these off and see if you can find the problem.

Warm air not emitted.

Engine coolant
Aspirator hose
Blower switch
Air mix actuator (Auto A/C), Temperature adjustment cable
(Manual A/C)
Heater core


Can anyone tell me what the "Aspirator Hose" is?

[Dookie]

Can anyone tell me what the "Aspirator Hose" is?

It's #17 on page 5..... http://www.subaru-car.ru/imp1/imp01_body_1.pdf

[Pinegrovesubaru]

UPDATE. I went to a junk yard and looked at a junker that already had half the dash pulled apart. The damper door is on one shaft but it had four plastic pieces molded to the shaft (one for each duct). Just for grins and giggles I tried to break this unit. I couldn't, not even with a pry bar. It is crazy strong! So I believe the likelihood of one of the pieces to break off the shaft is minimal.
I checked with the dealership and had a pleasant 30 minute discussion with the Subaru certified mechanic. He had no additional ideas. But he did say to get to the heater core does require removal of the entire dash and more. He's done a few and it usually takes about eight hours. I'm sure my taking apart the dash would result in broken trim pieces and since it is my wife's car, I decided I would not attempt it. But to have the dealer do it would be over $700 and I didn't want to spend that much on this problem.
Having no other options I decided to try the one last thing; I decided to back flush the heater coil. I disconnected both lines and using a garden hose and the hottest water my coal burner could produce flushed the coil. I did it in both directions and about a dozen times.
And believe it or not, this fixed the problem! I'm not sure how the Bar's Leak clogged only the passenger side of the coil, but it appears that is what happened. The air coming out of the driver's side is about 120 degrees F, the air on the passenger side is about 110 degrees F. Not exactly the same, but much better than only 90 degrees F.
I'm happy, my wife is happy, and a happy ending! :)

[New GT]

Why did you put Bars leak in your car? That stuff does more harm than good.

[Pinegrovesubaru]

An old time mechanic recommended Bar's Leak to me thirty years ago as a way to prevent miscellaneous leaks and to lubricate the water pump bearings.
I have been using it at every change of antifreeze on every vehicle I have had since 1980. I never had this problem on any vehicle, including the 95 Impreza and the 2002 Legacy.

The 2002 Legacy was consuming antifreeze slowly, about a pint a month. I know the history of head gasket leaks on Subaru's, but didn't want the time and expense of doing the heads.
So I added a second bottle of Bar's Leak.
Then I added a third bottle of "professiona"l Bar's Leak.
Then I added a bottle of Subaru Blue Goo. After a month the leak stopped. I know it is hard to believe but the heater and radiator are working fine. This was about 50,000 miles ago. The engine just turned 203,000 and besides a small oil leak it is doing fine.

What is amazing to me is the 2002 had three bottles of Bar's Leak and the it never affected the heater coil. The 2006 had one bottle of Bar's Leak and it blocked the coil. Weird.....

[Dookie]

Very interesting, I'm glad you were able to find the problem and fix it. That is a new one for me.

[TurboLegman]

An old time mechanic recommended Bar's Leak to me thirty years ago as a way to prevent miscellaneous leaks and to lubricate the water pump bearings.
I have been using it at every change of antifreeze on every vehicle I have had since 1980. I never had this problem on any vehicle, including the 95 Impreza and the 2002 Legacy.

The 2002 Legacy was consuming antifreeze slowly, about a pint a month. I know the history of head gasket leaks on Subaru's, but didn't want the time and expense of doing the heads.
So I added a second bottle of Bar's Leak.
Then I added a third bottle of "professiona"l Bar's Leak.
Then I added a bottle of Subaru Blue Goo. After a month the leak stopped. I know it is hard to believe but the heater and radiator are working fine. This was about 50,000 miles ago. The engine just turned 203,000 and besides a small oil leak it is doing fine.

What is amazing to me is the 2002 had three bottles of Bar's Leak and the it never affected the heater coil. The 2006 had one bottle of Bar's Leak and it blocked the coil. Weird.....
As an Oldtimer, I can tell you, the Bars Leak was good back when we were driving '40 Fords (wish I had my old one now) and '37 Dodges, but the heater cores used to be copper. Not now! The crap used for todays heater cores are just that, CRAP! Don't use the old additives that we used to use! When I was a kid, black pepper was a popular additive to stop leaks around a waterpump shaft and saw dust was used in the rear ends to stop a roar! Get my drift! Don't do it!:patriot:

[TSi+WRX]

How does Bars Leak compare with Holt's Radweld?

The reason I ask:

http://www.subaruforester.org/vbulletin/f88/holts-radweld-aka-subaru-coolant-conditioner-thoughts-65712/

"Subaru Conditioner."

^ A topic of persistent mystery!