I need to know the diameter size of the sensor temperature located in engine cylinder head, also tell me which tool I have to use to replace it.
I appreciate your prompt answer. thanks a lot.
What size engine? I know the 3.8s and 5.0s have the engine temperature sensor mounted on the intake manifold (the later SEFI 5.0s have it on the heater core pipe).
You should need a deep well socket or a "Line Wrench".
Your problem you probably have now is over coming the plastic connector "if" its the ECT sensor.
Make sure its not bad though, its easy to test if you can heat it up and follow the resistance readings in my diy link. lots of times the sensor collects garbage on the end that normally sits in the coolant and with this part being dirty, it can cause and insulating effect and not actually providing good data back to the computer.
For some reason i think i was forced to use a box in wrench to get it out but i may have also bent the wrench a little as well. This was before i had all my super deep well sockets.