Heater question?
Thread Starter
Racer
Joined: Mar 2011
Posts: 337
Likes: 1
From: Mechanicsville Md
Heater question?
I start my car and after it warms up the heater works fine and gets warm. I set the temp at 75 degrees manual or auto and it works fine but then it starts getting cooler. No codes get set. Any suggestions. The passenger side will continue to blow hot air with the passenger temp **** warm.
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
Well, I would think one or both actuators could be having an issue but I would expect to see codes. You did pull the codes from the DIC? Possible you have a blend door sticking but again, I would expect a code.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
If you use a mirror you can look under the dash and see the actuator. It looks like this:
There is a slot in the end of the door shaft that you can reference where its at at any given temp.
See if that shaft MOVES over time as you operate the HVAC System.
If it does,, you most likely have a cracked drive gear like this:
BC
There is a slot in the end of the door shaft that you can reference where its at at any given temp.
See if that shaft MOVES over time as you operate the HVAC System.
If it does,, you most likely have a cracked drive gear like this:
BC
Burning Brakes
Joined: Feb 2006
Posts: 1,085
Likes: 3
From: Ottawa Ontario, Canada
Holy cr@p, Bill, is there anything you don't have pictures of? 
I laughed when I read this - I was thinking the same thing this morning (just above freezing here). My '02 has done this for years, and only when the heater is required (when cold out). The car warms up, the heater fires up, the cabin gets warmer and then as it's getting to the point where it's warm it cools off a little. Not completely, but it's like if the HVAC is set to 75 it overshoots to 80 then cools back down to 75. Once it settles into a given temperature it seems fine.
I had it set at 73 and it would warm up and then cool off too far, so now I set it at 75 and it seems fine. Before, when set to 73, after the initial warming I could just bump the temp up to 75 and everything was OK.
Wierd. I wonder if our issues are the same. Bill, can you explain how the blender door actuator/cracked gear thingy affects the temp? What is this actuator called? Can a replacement be ordered?
I laughed when I read this - I was thinking the same thing this morning (just above freezing here). My '02 has done this for years, and only when the heater is required (when cold out). The car warms up, the heater fires up, the cabin gets warmer and then as it's getting to the point where it's warm it cools off a little. Not completely, but it's like if the HVAC is set to 75 it overshoots to 80 then cools back down to 75. Once it settles into a given temperature it seems fine.
I had it set at 73 and it would warm up and then cool off too far, so now I set it at 75 and it seems fine. Before, when set to 73, after the initial warming I could just bump the temp up to 75 and everything was OK.
Wierd. I wonder if our issues are the same. Bill, can you explain how the blender door actuator/cracked gear thingy affects the temp? What is this actuator called? Can a replacement be ordered?
Tech Contributor
Joined: Dec 2006
Posts: 10,962
Likes: 29
From: Van Buren Arkansas
Wounded Warrior Escort '11
The actuator is just that, an actuator...but sometimes referred to as a blend door controller and so on. All depends on the parts site you are looking at. There are two different ones, driver and passenger and have different part numbers.
Tech Contributor
Joined: Dec 1999
Posts: 32,910
Likes: 2,402
From: Anthony TX
CI 6,7,8,9,11 Vet
St. Jude Donor '08
Yep.... I have a few pictures!
The blend doors are TWO doors. They either cover the heater core opening OR the AC Evaporator core and any where in between to get a bland of warm or cool air. Ive never had an HVAC assembly apart but i have looked in there and seen the doors.
If you get your dash this far apart, you can use the vacuum actuator handle to open the upper vent and look down into the HVAC Duct and see the doors..
BC
The blend doors are TWO doors. They either cover the heater core opening OR the AC Evaporator core and any where in between to get a bland of warm or cool air. Ive never had an HVAC assembly apart but i have looked in there and seen the doors.
If you get your dash this far apart, you can use the vacuum actuator handle to open the upper vent and look down into the HVAC Duct and see the doors..
BC
Thread Starter
Racer
Joined: Mar 2011
Posts: 337
Likes: 1
From: Mechanicsville Md
Thanks, great pictures. Do you have pics for how to remove the dash? Thought I'd ask, you seem to have worked on everything. If I pull out the old actuator, is there a way to determine where the correct clocking of the new one should be or if I replace the gear, same question. How do I set the correct position? Again, Many. Thanks for the help
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