So I have an odd one, for me at least. My heater worked great last season, and now for this one, not so hot. Once the car warms up and it starts to blow some warm air, I get a little hot air out of the dash vents, and a bunch of cold air at the feet vents. My only guess is that one of my vacuum servos are blown, not working or got disconnected. I have the digital climate control and it appears to be in perfect condition. Is there any way to mend this problem without pulling my whole heater core out? Where should I start looking?

Thanks

 

be sure the vacuum hoses in the engine compartment are intact. Helps to give answers if you put in the year of the car and if engine is n/a or turbo. there are differences. without correct vacuum system does not work or at least very poorly. Just did my 86T and made all the difference.

 

I also had to replace vacuum lines under the hood on mine. I replaced the line from to the water **** and also the line that goes from the vacuum tank through the firewall. Mine blows hot, but sometimes does not switch from defrost to other settings...but just having hot air is better than what it was before! I'll sort out the rest in the spring.

 

I am having same problem, did you get it sorted?