Thanks for the good words.
It's all in the attitude!
My heater works sometime's other times I just get heat from the Def. with no blower. When it works with the blower the heat is luke warm at best.
I'm thinking that it might be vacuume lines and maybe the temp. sensor? I'm not real clear on what the mono valve does or should do. I did find a wire plug on it that wasn't pluged in, but that didn't do anything The A/C compressor is not working, in fact the belt has been removed. Would that make a differance? Is that really a GM part?
I got myself a mity-vac for the lines but can you just buy new lines by the foot or do you have to know which line to ask for at the parts dept.? Also do they have to be the hard lines or can you replace them with standard stuff?
Sorry about all the ?? but this is my first MB and the learning curve is a little flat right now!