A/C only blows out the defrost and floor vents
11-26-2008, 03:32 PM
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A/C only blows out the defrost and floor vents
Okay so for several months now my A/C or heat will only blow out of the defrost and floor vents, and I can't figure out what I did. I say what I did because I know I caused the problem. I installed a cb right on the dash paneling under the radio above the airbag box or whatever that thing is. Anyways I did not have any short screws handy so in a moment of genious I used some that were I think 2 - 2/1/2 inches long to drill the mounts in. The A/C still worked and everything was fine, no problems. But when I went to uninstall the cb mounts a few months later and remved the screws my A/C started only blowing out of the defrost and floo vents no matter the setting. Not knowing much about the system I really don't know what to be checking. I have checked the lines and assembly that you control the setting from and they seem to be in working order. Any ideas what I might have done?
11-26-2008, 06:36 PM
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The actuator that moves the vent doors to control that is just above and to the right of the gas pedal. The vacuum line that runs to it may have been damaged or maybe you hit the actuator with one of the screws but the screw was plugging the hole until you removed it. My actuator went bad last winter, I got a new one the other day and have to install it this weekend.
John
John
11-26-2008, 06:47 PM
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What he said. check the vacume lines. I had the same thing happen when installing a air dog fuel system. I knocked lose the main vacume line and lost everything.
dm01
dm01
11-26-2008, 11:00 PM
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Last time I removed the panel under the steering wheel and looked back there I noticed what looked like a black box. Was that the actuator? If that is it is there a secret to getting to that actuator to check it and the lines
11-27-2008, 06:11 AM
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The actuator is a small, silver, metal canister a little bigger in diameter than a "D" battery with a vacuum line hanging off the bottom. If you lay on your back on the driver's side floor with your head by the gas pedal you will see it. The easiest way to check it is to hook a vacuum gauge up to see if it holds vacuum, if it doesn't its no good. If it moves the arm when vacuum is applied and holds vacuum then its good. If you still can't find it I can try to snap a picture of mine.
John
John
11-27-2008, 07:50 AM
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check under your hood by the vacuum pump, the main hose will get knocked off sometimes, usually the cruise or 4x4 will not work either if you have lost main vacuum
11-27-2008, 10:10 PM
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I agree try the vac pump under the hood first then where it hooks to the fire wall if you have a vac pump it will make it easier to diagnose the canister under the dash
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11-28-2008, 12:46 AM
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I just got my System working again (mine was stuck on Defrost). Found out my Vacuum line was closed shut (due to running turbo with no downpipe...heated up the line and melted it closed, oops!). So I cut the bad piece out, installed a little compression fitting and now everything works again.
The line runs along the top of the hood/firewall, under the weather stripping stuff. Then it runs through the firewall to the upper right of the PCM.
The line runs along the top of the hood/firewall, under the weather stripping stuff. Then it runs through the firewall to the upper right of the PCM.
11-28-2008, 01:39 AM
#9
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Make sure the vac check valve is installed and if there is any oil in vac hoses. If there is oil in vac hoses then actuators need to be replaced.
11-28-2008, 03:08 PM
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Thanks for the input everyone, I will be checking all of these things when I get back home in a day, what does the vacuum line running by the turbo look like? I noticed there is a plastic looking smal line that has been broken by the around the turbo and exhaust manifold. I think though that it was broken well before the A/C started only blowing out of the defrost and floor vents. I will try to get a picture of it up.
11-28-2008, 03:44 PM
#11
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The black plastic line is probably the vacuum hose. Mine fell down and melted on the turbo. It was an easy fix. The line is about 1/8" in diameter or so and I just patched mine together and I have controls back. Try fixing that broken line.
11-29-2008, 03:33 PM
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Don't forget to check the obvious. I was having the same issue until today. When I took off the kick panel under the steering wheel I could see that the pin connecting the actuator arm to the door pivot was missing. One cotter pin solved my problem. Now I can get air out the panel too!
- Craig
- Craig