That's the cylinder head tenperature sensor.
If you are using a TS blower, try to use the orginal sensor and harness. Make sure the harness is insulted with a wire shroud. A little bit of loktite is good to. Just hand tight.
The new sensors are slightly longer than the old ones by 1/8". It makes a difference. They end up hitting the bottom of the blower manifold if they are too long and then press the wires against metal, causing them to short, fail safe happens, then you got to pull it all off and fix it.
It sucks.