Hot air blowing into car

[garyalanlane]

Hi my 89 Turbo has started to blow hot air through the heater vents into the car under hard acceleration even when the ac is on. Any ideas......? With thanks Gary

 

[robwright]

Possibly temperature flap clip has come adrift or heater control valve has failed or the vacuum line has popped off. If it is only under accelearion then your cooling system may wany bleeding. Any gurgling noises when you put your foot down?

 

[garyalanlane]

Cheers Rob. there are no gurgling noises. On the flap or vacuum line solutions I don't suppose these are easy fix solutions that the average diy mechanic could tackle. I don't even know where to begin. Are these easy accessible....? I have the repair manual cd's and I have replaced the dash in the past so could take this out again if access is a problem.

 

[Diver944]

The flap clip is easy to diagnose if you take out the glovebox liner because the clip is just to the right of the glovebox and secures two control rods in place. Remove the fuse to the glovebox light first as it always blows if you don't, then just remove the 6 or 7 tiny phillips screws that hold the liner in place. Slide it out and you'll see the rods and clip to the right.

The clip is a common failure and is about a pound from Porsche

 

[bertelli_1]

If it operates normally off boost then the fault will be the one way valve in the vacuum system. It'll be a little blue valve near the bulkhead (just follow the pipe from the vac resevoir.

 

[Northern924]

have a look at this page, explains it all....http://www.kronowit.com/porsches/944-heater-fix.html

And as it has bee said just a few quid from your OPC to buy new bits.

 

[garyalanlane]

Thanks guys it seems it was the clip. However now my heater doesn't seem to be getting as warm as before. Do I turn the heater on cold then push the flap up and click it in or turn it on hot and do the same....? Thanks again

 

[robwright]

You might have to calibrate the servo motor like so:

To send it the other way reverse the polarity. It's also a good way of testing the servo. The clips often break or detach as a result a seized servo motor. Principle is the same for all three flap servos.

 

[homesea]

When I did mine I turned the temp all the way up or down (cant remember) with the ignition on and watched the wheel bit spin round then pushed the flap all the way up and clicked the clip on.

Reading that again it sounds silly but kind of makes sence when your upside down in the footwell.

As it's been said on here many times remove the fuse for the glove box light before you take it apart as you will short the lamp!