I am checking my car for a rough idle when cold. I have just checked the wiring connection to the temperature sensor in the head. There are 4 wires going to it. The woring connector has numbers 1 to 4 stamped into the plastic next to the pins. The sensor in the head has a number 1 stamped next to one of the pins. My connector was fitted 180 degrees out from this so that the "number 1's" did not align.
Should they be aligned? It would seem logical - but the wiring is under tension to get the unit to align in this way. Strange. Any advice + advice on how to test the senor would be appreciated.

rgds