Motronic CTS (Coolant Temperature sensor): Bosch 0 280 130 026
@ –10°C the resistance should be 8.3 to 10.5 K.ohm
@ +20°C should be 2.2 to 2.7 K.ohm
@ +80°C should be 0.28 to 0.36 K.ohm
2.5k at 15c
This is the thread where it ended up being the fuel regulator.