AKchic: If you disconnect the power to the monovalve, you should get full heat. If you are not, then either the monovalve is stuck shut, or, your aux. pump is no longer wanting to pump. (follow the heater line to the aux pump - you can usually hear it buzzing/running with the starter key in the on position)

Snibble: I'm thinking that since the monovalve is in full heat mode with the power line disconnected (or engine off, for that matter), that the heat you are getting, is hot coolant flowing through there. Once you start the car, the monovalve closes (not sure how fast), but some hot coolant still gets by, and heats up the core. After a minute or two, you should feel cold air again. At least, that's what I am experiencing with my 300D.

AKchic: Good luck with keeping warm!

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It is a truism that almost any sect, cult, or religion will legislate its creed into law if it acquires the political power to do so. Robert A. Heinlein


09 Jetta TDI
1985 300D