blend door problem
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Originally Posted by vicsr2
The blend door diverts air from the vents to the defroster when accelarating
then back again when decelarating. Is the blend door vacuum operated?
then back again when decelarating. Is the blend door vacuum operated?
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Hello everybody (first post) Looks like I might have the same problem vicsr2. Got a 2003 Expedition E.B. with automatic climate control. My problem sounds like it maybe smiler but not sure. When my heater is on (usually 70 degrees or higher on the display screen heater is on etc.) it works fine, but as soon as I set it at a lower tempters down in the low 60,S something degree range I have the same problem as vicsr2. Why does it work ok in heater mode and not in the A/C mode, figured it would be defective in both modes? Under moderate to heavy acceleration it goes from blowing out the front vents to the defrosters, after acceleration is let up or steady speed is maintained it will go back to blowing in the front vents. Its very hot this time of the year, and the wife keeps reminding me of that fact, as if didn't know that already myself. So if anybody on this sight can help us as soon as possible it will make life more bearable. Thanks advance
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From: St Louis
Under moderate to heavy acceleration it goes from blowing out the front vents to the defrosters, after acceleration is let up or steady speed is maintained it will go back to blowing in the front vents.
Steve
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I disagree with the guy above me, but it's worth checking into (the vacuum lines). Your symptoms are very similar to mine. Your blend door is broken, like 10,000 others that I have heard and read about. Its a Ford problem with the design of many many Fords. Unfortunately you have to pull the dash and it took me 8 hours of work with air tools!
The reason the heat works is because the blend door is open, and the heat is coming right past the heater core. When in A/C mode, the door closes. Yours is broke, and therefore the A/C will not work unless you can hit the brakes pretty hard, (look for cars behind you before doing this). Then put your hand in front of the a/c vents. If you have ice cold A/C, the problem is your door. Make sure you put your fan speed at low, that is the only way my a/c would work.
The reason the heat works is because the blend door is open, and the heat is coming right past the heater core. When in A/C mode, the door closes. Yours is broke, and therefore the A/C will not work unless you can hit the brakes pretty hard, (look for cars behind you before doing this). Then put your hand in front of the a/c vents. If you have ice cold A/C, the problem is your door. Make sure you put your fan speed at low, that is the only way my a/c would work.
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I don't exactly have the problem you are describing 99ExpyProblems. I never need to slam on my brakes as you describe, just easing of the throttle will usually make it start blowing from the front vents apx 3-5 seconds. as for the tempter it still continues to blow somewhat cold when its blowing from defroster, but just recently started noticing the air not being as cold as it should be. Hope I don't have 2 deferent problems to deal with. checked the freon level 6 weeks ago and it was fine. if I have to remove the dash to fix this I will, but I am not looking forward to it. Hope its the vacuum line problem that [U]projectSHO89 is describing. I will try looking in the areas you mentioned, not sure about the under the dash you are describing. Wish me luck.
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FordDope, I had the same issues as you were having. I put it off for a year, and eventually the "slamming" on the brakes was the last ditch effort. It will slowly get worse in my opinion. Also, the "not as cold" that you are describing is from the blend door being partially open and allowing air across the heater core.
This is my guestimate, but the vacuum lines are definitely worth a look. When you turn the A/C from heat to cold, do you hear a "sucking" noise as it tries to close the blend door? You should hear a thud as the blend door closes.
This is my guestimate, but the vacuum lines are definitely worth a look. When you turn the A/C from heat to cold, do you hear a "sucking" noise as it tries to close the blend door? You should hear a thud as the blend door closes.
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From: Richmond, TX
99Expy......maybe you should read the original post. The problem YOU had is that typical of the blend door (no cold air). The problem the original poster has, IS vacuum related (air switches from front vents to defrost on accel).
To the original poster, look between the battery and the firewall, you will see a mess of vacuum lines, start there for your problem.
To the original poster, look between the battery and the firewall, you will see a mess of vacuum lines, start there for your problem.
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I was told there may be a way to fix the blend door by strategically cutting a hole in the side of the boax , installing the new door , and then siliconing the hole..HAs anyone seen pictures of this. Also does anyoe have the part number to the door 99 expedition w, eatc
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From: Richmond, TX
Originally Posted by infyre
I was told there may be a way to fix the blend door by strategically cutting a hole in the side of the boax , installing the new door , and then siliconing the hole..HAs anyone seen pictures of this. Also does anyoe have the part number to the door 99 expedition w, eatc
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Originally Posted by 01silvergt
99Expy......maybe you should read the original post. The problem YOU had is that typical of the blend door (no cold air). The problem the original poster has, IS vacuum related (air switches from front vents to defrost on accel).
To the original poster, look between the battery and the firewall, you will see a mess of vacuum lines, start there for your problem.
To the original poster, look between the battery and the firewall, you will see a mess of vacuum lines, start there for your problem.
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