With a/c on it still blows super hot! I see the compressor is coming on but stays blowing hot! The other day it worked briefly...the system is not cycling either.

 

What I mean by cycling is the compressor stays turning..not off and on like its out of freon

 

Are you SURE the A/C is not working? These cars have a tendency to deveop a problem with the valves that control heater water. Mine will "stick" and give me 100% full on heat on the driver's side once in a while. The only way to stop it, is to shut the car off, then restart it - fixed. (Acts up when I turn the heat **** up fully, then when I turn it down, the valve seems to stick).

So, is the A/C really not working, or is the heat staying on?

If the heat is not staying on, and you can tell the pump is engaging, then either the condenser up ahead of the radiator is FULL of leaves, the fan isn't running (if it cools as you speed up, that would indicate the fan under the hood is not running when it should, but this would also imply overheating of the engine at times would also happen) or the system has leaked out.

 

The compressor clutch is engaging and stays running so I'm good there..it's got to be a sticking valve problem

 

Hey Mark, any idea what happens if you simply unplug the connector to the heater valves ?
It is a pulse width signal to them, I would assume they would shut, but now that I think about it, since these are German cars, maybe they go full open ?

 

Well Mark....?? I'm anxious to hear this

 

Where is this switch located?

 

Sounds more like a blend door issue. "In a blend-air system, a blend door controls the amount of unconditioned air (or cooled air from the evaporator) that is allowed to flow through and around, the heater core. A temperature control on the A/C heater control panel determines the discharge air temperature by energizing the blend door actuator, which operates the blend door. This allows an almost immediate control of the output air temperature of the system."