you're both right

8v sensor is in the oil filter housing, 16v is on the back of the head. The sensor has a spade connector on it, and the wire colour is black/green.
The oil temp will read --- below 50 degrees, if like you say it still reads --- above this, then either the wiring or the sensor is duff.
To check the wiring, simply earth the sensor lead to the engine, the MFA display should shoot up to max. If not you have a break in the wire, and if it does, replace the oil sensor
