See the diagram below for engine coolant temp sensor.
Disconecting it isa not going to do anything You need to determine if the temp sensor is sending the correct signal to the ECM
You have to back probe the plug at the white and black wire and check the voltage with a volt meter.
Cold engine (70 degrees F) voltage should be about 3.0 volts
You can also try conecting the pins together when engine is hot if the engine clears out and runs better replace the sensor.
Full warmed engine 190 degrees Voltage should be 0.7 volts
Is the engine warming up to full temp? if it is not you may have a stuck open themostat.
Is the check engine light coming on?
If so you need to get the codes .