Please note that that "crack" in the sensor might be TERMINAL to your
motor!
I had my motor go south once. Post-mortem analysis revealed that it had a
serious overheating situation. The cause was a water leak in the oil
cooler, and during the night all water dripped away so when I drove the
van the next day it had a major meltdown after 15 minutes.
And why didn't the coolant level warning system warn me?
Because the sensor had a crack, causing coolant to ooze out slowly and
dampen the wiring, so that even if there was no coolant the system thought
there was...:=(
And the dash temp meter did't indicate a problem either, because the
sensor was measuring AIR temperature (the thermostat housing, where it is
installed, was drained too...).
Lousy engineering from those Germans IMO.
Solution?
Put a temp sensor on the motor head, like in the air cooled.
With a LOUD buzzer...:-)