HEAT comes ON and OFF > HELP!
 

Hi, I have a 1985 1/2 Porsche 944 with almost 100K. For the past couple months hot air will randomly blow out of the vents. Sometimes I start the car and drive it for a while and then all of a sudden hot air is coming through vents and other times it seems to happen right at start up. One day it was 90 degrees out, I am on the freeway and hot air is blowing through the vents even though I have the fan speed set at zero (on the dash climate control). I used contact cleaner on the climate control TEMPERATURE knob and still having problem.
Am I on the right track??? Should I replace the TEMPERATURE knob (blue-cold/red-hot)????
OTHER INFO: Car has seemed to be running a little warmer this year ... had new thermostat last year. Put new Bosch Platinum plugs in this spring (New WR7DP - Old WR8DP) ... A/C needs charged ... (probably not related but just in case)
DOES THIS CAR HAVE AN AUTOMATIC FEATURE IF THE CAR IS RUNNING TOO HOT IT AUTOMATICALLY SHOOTS HOT AIR INTO THE CABIN TO REDUCE ENGINE TEMPERATURE??? That could explain the 90 degree day on the freeway but wouldn't explain the times it blows hot almost immediately after start up. PLEASE HELP !!!!

Hi,

I have a 1985 1/2 porsche 944 with almost look.

For the past couple months hot air will randomly blow out of the vents.

sometimes I start the car and drive it for a while and then all of sudden hot

air is coming through vents and other times it seems to happen right, start up.

I really appreciate with this forum.

Thank you.

view for free system

There is a plastic clip on the drivers side of the HVAC unit that breaks and the selector rod pops out. Replace the clip and retaining piece, and you should be good to go. All of about 6 bucks.

If you go to clarks-garage.com and open his garage shop manual, there should be a section on heater or climate control, etc. He has a writeup with pictures.