Alright, here is the deal. I drive all over the place. Lately the A/C won't blow cold air. I checked the R134a level and it is fine. The compressor kicks on and stays on. The air coming out is right at ambient. But if i turn off the air all together, then what feels like super heated air "leaks" by and into the car. It feels hot enough to burn you.
I am willing to try just about anything.
Thanks

A poor electrical connection at the heater monovalve will cause the situation that you describe.

Where is this heater monovalve you described.

anyone?

Do a search for "mono valve" here in the Diesel Discussion. You will find photos and everything. The mono valve is "open" (lets hot coolant flow into the heater) when there is no power to it. When the ACC sends 12 Volts to the mono valve, it closes. If the mono valve is stuck open, you get hot air and cold air mixing together, hence the situation you describe. This situation has been discussed many times here, pictures of fixing and all you need to know, just search.

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"Buster" in the '95

Our all-Diesel family
1996 E300D (W210) . .338,000 miles Wife's car
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