190E Climate Control Issues - Please Advise.

[Dustin.]

On my recently purchased 1991 190E 2.6, I've been trying to figure out these problems with the climate control:

(1) The heat doesn't seem to work at all. It doesn't matter which vent selection I choose, only cold air comes out. The auxiliary water pump seems to be working, not sure how I would check if the heater core is working.Any other ideas as to what I can check?

(2) The blower motor works well, but i've only been able to get air to come out of the center vents. Nothing comes out of the floor vents or dash vents. I've read somewhere this could be a "blend air door" or possibly a vacuum line... any ideas?

Thanks for the help.

[lsmalley]

try checking out the heater check valve. under the leaf cage on the passenger side. have to undo the windshield wiper to gain access

[RobertFini]

We regularly have a similar problem on our 1984 190E Stage Rally racer - yes we still have the factory climate control unit in a race car, although we have removed the air conditioning compressor, condenser, evaporator and other associated bits for weight savings.

There is a connector on the back of the climate control unit in the dashboard that works itself loose and pops off, rendering the system inoperative - no fan, no heat, nothing. The air coming from the center vents is just outside air being force-fed by the movement of the car.

One of these days, I'm going to develop a method to positively lock this connector in place, but for the time being I just reach behind the unit and reconnect it; it helps to know what you're looking for when you're doing it by feel, which I unfortunately am familiar enough to do.

Your trouble might be something different, but I recommend that you check the simple stuff first.

Best Regards,
Rob