len lobaito

I have a '91 c2 and there is very little air coming out of the center dash vent even with the fan on high.

The control slide is working properly and turning the rheostat in the boot.

There is normal air flow from the other two side deflectors and foot wells.

I am having a hard time finding any diagrams of the ventilation system. Any ideas?

jimq

I have the same problem sort of. Mine doesnt blow out of the passanger side center vent. Havent delt with it yet as I get the extra air. The GF says it needs to be fixed. My thinking is a servo is stuck or burned out. Maybe we will get some guideance here Was thinking about digging into it this weekend to see whats up.

Heirsh

wow, I just realized the other day my center right vent doesnt work as well. I just assumed they were both the same, but I guess they have an individual supply for each, even though they are connected. I wonder why they were made like this.

Smokin

I've read a quite a few posts on this. If you search for "servo" you are liable to turn up all sorts of info on the subject. As I recall... There are three servos that control all the stuff back there. I believe they (the broken ones) will need to be reconditioned (if possible) or replaced.

Good Luck

Kismet

I have a vague recollection that a Hammer will detect faulty heater servos.

Regards
Tony

len lobaito

The 'servo' thread does turn up many hits and I am wadeing through them. No luck yet.

The 'Hammer' may show the errant servo but you should easily be able to see which one is not moving if you knew which one to look for.

Thanks to all........I will keep you posted and please let me know if you turn anything up on the subject.........( a clear diagram of what works what would be perfect.)

With summer here, a cool breeze of air conditioning from the center vent would be a welcome change.

Thanks again,

--Len

jimq

I printed out a repair thing on P-CAR.com
Check it out. Shows how to fix and remove the servos. Also i will check Adrians book to see if it has any thing helpfull in it.

EDIT: oops wrong site. Try this one
http://porsche964.co.uk/

len lobaito

Thanks Jim.......I've got that one already...........It will help once I have figured out which servo to remove. There is very little room to work in that area of the boot and I would probably wind up pulling all of them before hitting the right one.


Thanks again,

--Len

l3sl13

What, you mean they are supposed to work?

jimq

Hey maybe you are on to something! Maybe it was designed to only blow out of the center drivers side

Eric Kessel

Len,
Did you read the article on the http://porsche964.co.uk/technical/servos.htm
site? It has a picture showing the climate controller face, and explains which servo does what....... you probably want to look at the servos that move with the two sliders..........

len lobaito

Yes l3sl13, they are supposed to work

No jimq, there are verticle wheels on both the left and right of the center vent which individually control center vent air flow for the dirver and passenger. Each wheel works independantly of the other but mine are both open and still no air.

Eric,

I have studied the pictures, which are very helpful, and they fntion in my car as follows:

1- Funtions as you move the upper slider back and forth. There is no connection to an arm at the rear just as in the photo.
2- and 4 - move with the temperature dial - from cold to hot.
3 - does not move - as far as I can see, but I do not know what is supposed to make it move.
5- moves with the lower slide control.

I do not know if there is a piece missing and has fallen into the lower boot or if number 3 should be connected to something else or it could need to be rebuilt.

Thanks again for your help...........I'm still at it..........
--Len

gregC2

I have the same problem of lots of center air from the left half of the center vent and very little for the right side, center. When I first discovered it on my car, 10 years ago, I went into the show room where there were 4 other 964's, and two of them worked correctly (even air from both halves) and two of them didn't. Since it was under warranty, I had it looked at with no resolution other than they wanted to put some cardboard down the vent to redirect the air more evenly (thanks but no thanks). Had the zone rep. from Porsche come down and look; he'd never heard of the problem and couldn't find a resolution. I got the feeling that PCNA didn't really care about this "minor" of a problem. So, when I have a passenger, I'll turn off my half so they can have the cooler air. Hey, it's a "driver's car", isn't it? Cool down who the car is built for . . . good luck.

jimq

Yea Greg looking at it for a bit and the servo picture it looks like it all comes from the same place and should have maybe a baffel or something in there. Gonna look at PET later to see if I can get a idea how it works from there. It is strange that most of us say its the center passenger side that is not blowing hard.

Eric Kessel

Len,
From the picture, servo # 3 is for the fresh air flapper. It will move when the recirculate button is pressed. The connection to it is directly below the servo, similar to the connection on # 4, but below.

Does this help? I had a bad servo # 3, but the only way I knew was from the fault codes. I ended up buying a whole used assembly that had the fans, and servos off e-bay since it was cheaper than getting a new servo from the dealer. If you need a piece of the linkage, or a better picture, let me know.......