heater problem
 

87 944 N/A
Heater when on full heat cycles cool and warm air. Any ideas?

Do you have the window down? The newer model 944 heating units have a thermal sensor in the cab (that thing in the dash that looks like a teeniny speaker, but isn't) that tells the hot/cool guy to send in more heat or not. The temp on your temp select is the temp that your car will try to keep it at. If you have a window open, you feel the coolness, but your sensor doesn't, so when you reach 40&degC (provided that you have selected the temperature 40&degC as your target temp) at the dash, it will quit sending heat. When temp sensors feels that it's getting too darn cold inside, it'll send more heat. <p>I say this because when I have my window down and the heater on, I feel the heater cycling warm/not warm very rapidly. I could be wrong.