No mono valve .... but I started looking around. I took off the plastic cowel cover (for lack of better description) and found that the two hoses that go into the heater core and the coming out have been by-passed!
Some took a long hose and intercepted the inlet and connected to the outgoing. There was no coolant going to the heater core.
Sooo the good news is I know why .... the bad news is why. I am afraid of the the second why. Sounds like I have a .... I almost hate to use the words ..... a heater core .... problem. I already have the lower dash down so I can see where one of the pipes goes into it on the driver's side.
I am attaching the regular hoses, top it off with coolant, get her warm and then see ..... wish me luck.
I understand a replacement of said part can be quite lengthy .....
'03 E320 Wagon-Sold
'95 E320 Wagon-Went to Ex
'93 190E 2.6-Wrecked
'91 300E-Went to Ex
'65 911 Coupe (#302580)