I checked out the heat. from cold, sensor 3 and 4 were saying +/- degree of what my infrared thermometer said the temp in the car said it was.
After I warmed the car up with the heaters on max, register 3 said it was about 70C, and the passenger side was saying 35-37.
I checked the hoses off the duovalve. the bottom outside (side closest to the fender) hose and the center hose were about 35C, and the bottom inside hose, and the top hose were 70-80C. I'm thinking the duovlave is at fault. I picked up a second one from the junkyard. I figure if I take that apart, and take a good side from it, my heat should work again.
Haven't checked the A/C pressure yet. The low pressure fitting is in the front, right next to the ac cooler, isn't it??

__________________
All it takes for evil to prevail is for good men to stand by and do nothing.

Too many people tip toe through life, never attempting or doing anything great, hoping to make it safely to death... Bob Proctor

'95 S320 LWB
'87 300SDL
'04 E500 wagon 4matic