HVAC selector switch stuck on "feet" setting
Thread Starter
Racer
Joined: Sep 2008
Posts: 446
Likes: 1
From: Phillipsburg New Jersey
HVAC selector switch stuck on "feet" setting
hey guys i was wondering if someone could help me out... my 99 coupe's HVAC position selector is stuck on the feet setting, meaning defrost and all other positions are inop.(its NOT dual climate control )this just happened tonight, and it worked fine up until right now. i can turn the **** freely without hearing any change (vacuum) in the switch. any advice? also, my blower fan only works on speeds 4 and 5, im guessing the resistor is bad? thank you in advance for any help!! -Jeremy
Thread Starter
Racer
Joined: Sep 2008
Posts: 446
Likes: 1
From: Phillipsburg New Jersey
i just went and checked a few things and read some threads on this about the vac leak under the battery. my question is, if i have good vacuum at the line under the passengerside dash, that goes into the purple vacuum line, do i need to check all the other underhood possibilities? (intake manifold, under battery, vacuum canister, etc) the **** on my hvac head just turns freely like its not doing anything, just wondering if the head is bad, or if theres another vacuum connection to check...
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
SeaFive,I'd be curious to know the answer to that same question...??
If you have vacuum behind the firewall in the passenger foot well, then you can be sure that all the lines behind the intake manifold and running down into the canister behind the fender are all okay?
How much vacuum should the gage be running?
Thanks,
Donnie
Le Mans Master
Joined: May 2006
Posts: 5,987
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From: DuBois PA
St. Jude Donor '11-'12-'13-'14-'15
If you have vaccum at your vaccum control valve then there's no need to check under the hood.
I'm not familiar with the single zone head unit, and I'm in uncharted waters here sorry. This free spinning feeling... is it different from when it did work? I assume you checked the **** to make sure it isn't hogged out.
Tim
I'm not familiar with the single zone head unit, and I'm in uncharted waters here sorry. This free spinning feeling... is it different from when it did work? I assume you checked the **** to make sure it isn't hogged out.
Tim
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Thread Starter
Racer
Joined: Sep 2008
Posts: 446
Likes: 1
From: Phillipsburg New Jersey
If you have vaccum at your vaccum control valve then there's no need to check under the hood.
I'm not familiar with the single zone head unit, and I'm in uncharted waters here sorry. This free spinning feeling... is it different from when it did work? I assume you checked the **** to make sure it isn't hogged out.
Tim
I'm not familiar with the single zone head unit, and I'm in uncharted waters here sorry. This free spinning feeling... is it different from when it did work? I assume you checked the **** to make sure it isn't hogged out.
Tim
ok..forgive my ignorance! it was the damn **** the whole time.im a technician by trade, and i couldnt figure that out the first time around? LOL... but thanks for the help. yeah, the **** was just cracked and free spinning on the shaft. probably from someone over turning the **** over the years. sorry to get so technical about such an overlook! -Jeremy
oh and i would assume that for those with the actual vac leak, if the first thing you do is check the connection at the hose that goes into the purple line and you have good vacuum, its safe to say youre not looking at a vacuum issue. just seems like a great first spot to start out for those trying to diagnose.
Melting Slicks
Joined: Sep 2006
Posts: 2,736
Likes: 7
From: Redding CA
Actually when there's a small vacuum leak, it will usually blow about 30% of the air out of each vent no matter what...
The whole time that my car had the vacuum leak, no matter what mode setting I had the car on the vents would all blow out an equal amount of air. The fan speed would change but it wouldn't switch the vents of course.
No biggie but I just thought that I'd throw that in because that's the way my car was stuck for months and I'd talked to a few other members that had the same issue.
It's more like without vacuum the door just stays all the way open and doesn't "direct" the air at all, it just blows it out.
DZ
The whole time that my car had the vacuum leak, no matter what mode setting I had the car on the vents would all blow out an equal amount of air. The fan speed would change but it wouldn't switch the vents of course.
No biggie but I just thought that I'd throw that in because that's the way my car was stuck for months and I'd talked to a few other members that had the same issue.
It's more like without vacuum the door just stays all the way open and doesn't "direct" the air at all, it just blows it out.
DZ
Tech Contributor
Joined: Jan 2007
Posts: 19,475
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From: Dyer, IN
4th Gear
Joined: Sep 2013
Posts: 4
Likes: 0
where was the vacuum leak located?
Actually when there's a small vacuum leak, it will usually blow about 30% of the air out of each vent no matter what...
The whole time that my car had the vacuum leak, no matter what mode setting I had the car on the vents would all blow out an equal amount of air. The fan speed would change but it wouldn't switch the vents of course.
No biggie but I just thought that I'd throw that in because that's the way my car was stuck for months and I'd talked to a few other members that had the same issue.
It's more like without vacuum the door just stays all the way open and doesn't "direct" the air at all, it just blows it out.
DZ
The whole time that my car had the vacuum leak, no matter what mode setting I had the car on the vents would all blow out an equal amount of air. The fan speed would change but it wouldn't switch the vents of course.
No biggie but I just thought that I'd throw that in because that's the way my car was stuck for months and I'd talked to a few other members that had the same issue.
It's more like without vacuum the door just stays all the way open and doesn't "direct" the air at all, it just blows it out.
DZ
4th Gear
Joined: Sep 2013
Posts: 4
Likes: 0
vac leak
Thanks for the quick response. Are we talking about a leak at the rear portion of the manifold intake gasket or simply a vacuum hose dry rotting etc. ? I'm not familiar (yet) with what exactly is back there and with such limited access its hard to tell. Thanks again for the help!