Join Date: Mar 2009
Location: Gulf Breeze, FL
The Engine Coolant Temperature (ECT) sensor is located on the front of the intake manifold, passenger side of the upper radiator hose, and just behind the cover that hides your timing. It is a 19mm socket and to get it out you should drain about a gallon of coolant using the petcock on the passenger side of the radiator, disconnect the upper radiator hose and remove the upper timing cover. This is a 2 wire sensor.
The water temperature sensor is just for the gauge and it is located on the back of the intake under all that crap. If your gauge is working then this sensor works and there is no need to get down to it. If you do have to get down to it you either have to be really squirrely or you need to take the upper and lower plenum off to succcessfully get a socket on it. This is a 1 wire "sensor". All this does is provide a ground for your temperature gauge on the dash.
2002 Tacoma with some dents.