I recently lost some coolant when my temp sensor came out of the thermostat housing.
I assumed I had ost a lot of coolant since the refill and top up tanks were completely empty and nothing more was dripping from the sensor mounting hole.
So I filled the refill tank to the brim and ran the engine and it only went down maybe 2 inches.
I did open the bleed valve and set the front and rear heater controls to ON.
Also, no coolant ever came out of the bleed valve and according to my Haynes manual it should have.
What did I do wrong, if anything. I'd prefer not to have to bleed the radiator unless its absolutely necessary.

David (1987 Wolfsburg)

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