My vents constantly blow hot air? why

[jkrustchinsky]

What isnt functioning properly that constantly blows hot air into my 944 n/a 87' cabin. Thanks Josh

[Techno Duck]

Plastic clip is probably broken. Search for 'plastic heater clip' and a multitude of threads will turn up.

[Tidybuoy]

Also check your Brake Booster Check Valve. There is a tiny port and the vacuum line that connects to it controls the heating system. I accidently broke mine well wiping down the engine and my heater was stuckl on until I fixed it.

Vern

[scottcip1562]

Check you heater control valve. Part number from our host.

944-572-085-02-M53

[Dantilla]

Originally Posted by Techno Duck

Plastic clip is probably broken.

Stick your head under the dash, towards the center. If there is a little shaft dangling, it's because the plastic clip that holds it to the hot/cold mixer valve broke, leaving the valve in the full hot position. The clips are getting brittle by now.

[maxhofer]

I had the same problem in my 944 n/a 1/'85. Turned out to be a faulty heater control valve. The valve was worn and would not completely shut off the hot water/fluid going into the heater, thus the heater radiator (or heat exchanger) was permanently producing hot air .
Bought a new valve from our host, replaced it and the problem was solved.

[maxhofer]

Originally Posted by scottcip1562

Check you heater control valve. Part number from our host.

944-572-085-02-M53

I believe that part number is for cars up to 1/85, for his '87 the part number seems to be

928-574-573-03-M53

[hpservertech]

wrong area.

[nize]

+1 on the heater control check valve.