1993 190e 2.3 - No Heat ?

It is not the heater core... it is most likely to be your aux water pump failure. It is the little pump with heater hose on the passenger side of the hood area. If you see leaking there... that is it.

What is this pump how is it driven electric ?? I don't think I have one I have a UK 1989 190E 2.0lt and it has the same symptoms The Heater Matrix is 95% certainly clear I Flushed it with a running hose after running a Radiator Flush chemicals first for 3 days water came out clear at the same rate out as going in BOTH ways, Fitted new Thermostat Car warms up quickly to 80deg when running at street legal speeds. goes above to 95deg if sat in traffic for 10 - 15minutes On UK drivers side there is a Monovalve that I am going to change Not leaking but this is fully open all the time Could it be Water pump again no problems driving car, no water leaks

190E usually has electric aux water pump as the engine water pump is too small to send some coolant to the heater core. Follow your heater hose all the way to the water pump... surely you must have some sort of extra pump in between.

Huh, I thought this was just a pre-heat kind of thing? I know i have seen a couple of cars at least with this electric pump removed/bypassed?

Could also be a problem with the temperature selector on the dash...

Marty