Lack of Airflow on heat, but not on cold?

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Slicer89

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This winter has been hell for us in the Montana, Not only does it run cold (Like, Below the first mark on the temp gauge) when it finally does warm up, The damn vents barely blow any air out on hot - The back air works great, And the front air works decent on Cold - But not on hot, I replaced the cabin air filter, I event took a air compressor and blew some crap out - Didn't make ANY difference.


Any ideas? The air that does come out, When the van is finally warmed up (Over the first tick mark above 160) the air coming out is definitely warm - Just not alot of it

And what would cause it to run.. so, cold? And take so long to warm up? Can't be a lack of fluid, because that would cause it to overheat, same if it were a bad waterpump

Someone told me to put some cardboard in front of the radiator to cover some of it - Seeing as the temps up here can get well into the negatives, it will still allow airflow just not as much
 
Air in the cooling system would cause your heater to not perform properly, however it would not effect the air flow. A blend door that does not fully close or a build up of leaves and debris would reduce the amount of air coming from your dash,

first you need to make sure no air is bleeding through the floor vents or defrost vents.

shine a flash light down the dash vents to see if any paper, debris or foam rubber is just on the other side of any of the vents, this would indicate some of the sealing foam has deteriorated allowing air flow to escape under the dash.

when people change their cabin filters they seem to always just pull it out through the thin slot that is just big enough to fit the filter but not the mound of leaves and debris sitting on top of it, causing all this extra debris to get scraped off and fall down on the blower wheel then the blower grinds this mess up and shoots it into the Heater core housing or AC evaporator housing clogging up either side. ( depending on what was being used at the time of service AC or Heat.

When changing the cabin filter the factory allows enough service time to suck the debris out through the cowl with a vacuum before the filter is removed this insures that the filter can be installed properly covering the opening these filters are flimsy and many times need to be pulled into place from the top to seal the cabin off from this debris.

the blower is easy to remove on a Montana it wouldn't take to much to stick a cell phone in there and take a video of what it looks like in the housing.

if you see any debris to cure the problem you may need to remove the heater core and or evaporator housing and clean everything up to get it to perform like it once used to.

The heater core may also need to be flushed along with the cooling system,

If the cooling system has been topped of with tap water or incompatible coolant you may have a considerable amount of corrosion accumulated in the heater core, hoses and coolant jackets and ports of the engine and radiator.
 
EaOutlaw said:
Air in the cooling system would cause your heater to not perform properly, however it would not effect the air flow. A blend door that does not fully close or a build up of leaves and debris would reduce the amount of air coming from your dash,

first you need to make sure no air is bleeding through the floor vents or defrost vents.

shine a flash light down the dash vents to see if any paper, debris or foam rubber is just on the other side of any of the vents, this would indicate some of the sealing foam has deteriorated allowing air flow to escape under the dash.

when people change their cabin filters they seem to always just pull it out through the thin slot that is just big enough to fit the filter but not the mound of leaves and debris sitting on top of it, causing all this extra debris to get scraped off and fall down on the blower wheel then the blower grinds this mess up and shoots it into the Heater core housing or AC evaporator housing clogging up either side. ( depending on what was being used at the time of service AC or Heat.

When changing the cabin filter the factory allows enough service time to suck the debris out through the cowl with a vacuum before the filter is removed this insures that the filter can be installed properly covering the opening these filters are flimsy and many times need to be pulled into place from the top to seal the cabin off from this debris.

the blower is easy to remove on a Montana it wouldn't take to much to stick a cell phone in there and take a video of what it looks like in the housing.

if you see any debris to cure the problem you may need to remove the heater core and or evaporator housing and clean everything up to get it to perform like it once used to.

The heater core may also need to be flushed along with the cooling system,

If the cooling system has been topped of with tap water or incompatible coolant you may have a considerable amount of corrosion accumulated in the heater core, hoses and coolant jackets and ports of the engine and radiator.
Click to expand...


There isn't any leaves or debris in the vents, Has I stated, the air blows alot better once it's on cold / cool.

I've blown out a little crap with an air compressor and shop vac, but it didn't help.
 
You have two sections one side for the AC evaporator and one side for the heater core the evaporator side may be semi clear with little to no debris.

There is a good chance the heater core side may be full of debris or even a rats nest. which will block the flow of air. blowing it out from the outside in will not remove all the debris if any is present.

Since you said you saw some debris come out when attempting to clean it this means at one point someone serviced the Cabin filter improperly, this debris either went into the evaporator side or the heater core side how bad it is can only be determined with a visual inspection.

I am not sure what else to say,there is no magic here if you have low air flow on heat only it must be blocked with debris or some foreign object.
______________________________
 
Since you didn't mention the year of your vehicle it is hard to tell if this fix or TSb applies to your vehicle.
Reading what the OP of the post you provided a link to this would be the next viable option for you to look into.

If you purchase a subscription to alldata which includes updated TSBs, recalls plus troubleshooting procedures and flow charts you will have any and all information you need to repair this on your own,

Letting us know that you had a inspection camera in the case and viewed the Heater core would have saved me a bunch of typing.

You have to eliminate the common problems before getting too technical, since you have this handled I will no longer respond to your request for help.

Thanks for being a typical jerk to the only person willing to try and help you.
 
Sorry, It's a 2000 Pontiac Montana... Base model.

I just NOW went and looked with an inspection camera, Thus why I didn't post it earlier.

I don't see how I was being a jerk, I really really really have no ****ing clue where you got that I was being a jerk. I've done some research and checked a few things, But was looking for advice on what else I can check.
 
Hello !
Perhaps not working an electric actuator damper position. (see diagram)

10909973.jpg


Video replacing electric actuator damper position. The system of heating and air conditioning Opel Sintra, Chevrolet Venture , Pontiac Montana - the same (1997 - 2004)
http://www.youtube.com/watch?v=cO2VMQRyEH4
______________________________
 
sergeimoskva said:
Hello !
Perhaps not working an electric actuator damper position. (see diagram)

10909973.jpg


Video replacing electric actuator damper position. The system of heating and air conditioning Opel Sintra, Chevrolet Venture , Pontiac Montana - the same (1997 - 2004)
http://www.youtube.com/watch?v=cO2VMQRyEH4
Click to expand...

I read this on another thread I found on here, and most people just unplugged it and left it open. I don't have the money right now to replace the unit.
 
are you sure you have a 195 degree thermostat and that it is working and not stuck open?
 
melsg5 said:
are you sure you have a 195 degree thermostat and that it is working and not stuck open?
Click to expand...

I'm wondering if it's stuck open.... I seen where it is and have no idea how I'll replace it.
______________________________
 
Slicer89 said:
This winter has been hell for us in the Montana, Not only does it run cold (Like, Below the first mark on the temp gauge) when it finally does warm up, The damn vents barely blow any air out on hot - The back air works great, And the front air works decent on Cold - But not on hot, I replaced the cabin air filter, I event took a air compressor and blew some crap out - Didn't make ANY difference.


Any ideas? The air that does come out, When the van is finally warmed up (Over the first tick mark above 160) the air coming out is definitely warm - Just not alot of it

And what would cause it to run.. so, cold? And take so long to warm up? Can't be a lack of fluid, because that would cause it to overheat, same if it were a bad waterpump

Someone told me to put some cardboard in front of the radiator to cover some of it - Seeing as the temps up here can get well into the negatives, it will still allow airflow just not as much
Click to expand...

right from your owners manual found online http://www.pontiac.com/owners/owner_resources/manuals.html


If you have the optional engine coolant heater and use it
during cold weather, 0F (-18C) or lower, your heating
system will provide heat more quickly because the
engine coolant is already warmed. See “Engine Coolant
Heater” in the Index.

Rear Climate Control (Option)
If you have the optional rear climate control, the rear
seat passengers can control the temperature and the
amount of air directed to the rear of the vehicle. You can
also adjust the amount of air directed to the rear of the
vehicle using the front fan knob.
When it’s cold outside, set the main climate control
knob to LOWER, DEFOG or DEFROST, to send air to
the rear of the vehicle through the lower vents.
Set the main climate control mode knob to UPPER or
BI-LEVEL to send air to the rear of the vehicle through
the headliner outlets.
To send conditioned air to the rear of the vehicle, press
the A/C button (the light will glow) on the main climate
controls. If you do not select A/C, air directed to the rear
of the vehicle will be cabin temperature

Keep the area around the base of the center instrument
panel console and the area between and under the front
seats free of objects that would obstruct airflow to the
rear of the vehicle.

Turn the fan to the desired setting for the amount of air
to be directed to the rear of the vehicle. The temperature
of the air will be the same as the air in the front of the
vehicle. The rear fan control in the instrument panel
switchbank has an “R” setting which allows the rear
passengers to use the rear climate control knobs to
adjust the air through the rear air outlets.

To maximize airflow through the rear heater outlet, place
the left bucket seat in the second row in the forward
position (see “Adjusting Rear Seats” in the Index).

what I get from this is you need to use or buy a block heater, with the added coolant from the rear system and hoses this vehicle will take a longer time to warm up. added to the extreme cold you encounter it makes sense that you should be using a block heater if one is equipped if not buy one.

second thing I get from the manual is that the passengers in the rear can pull air away from the front of the dash by design.

So if no one is with you adjust the rear controls to lessen this effect

also make sure that all the intakes for recirculated air unobstructed.

All these other post regarding modifying your damper or permanently closing it may not apply to your vehicle if the adjustments in the rear are what is causing the lack of air flow in the front.

There is a lot of information in the owners manual I suggest you read it before hacking up your vehicle and buy a service manual to help you troubleshoot any problems that cannot be solved by operating the vehicle controls properly

BTW when you posted this " I found this on here and was wondering if anyone else can chime in how the truth: "

I took this as you being disrespectful.
 
Thermostat

sergeimoskva said:
Hi !
If I get you right
... His rear heater is working, then the thermostat is working.
Click to expand...

The OP stated the temperature gauge just goes over 160 which I assumed could be a thermostat issue.
______________________________
 
It goes to the first tick mark over 160, and when I drive it hovers between the two, if I let it sit and idle for a while it will get up to a half, sometimes over half - As soon as I drive though it goes back down to the tick mark over 160, or below.
 
what is the average ambient temperature you encounter this time of year?
 
Brrrrr fn Brrrr LOL

Does your vehicle have a block heater?

what about the other things mentioned in the manual did any of that help?
 
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