Where is my coolant temp sensor on my 2001 firebird 3.8

Here's a link with pictures,should be the same as your year. Location of coolant temp sensor 2001 Caravan 3 3FF DodgeForum com

Usually threaded in thermostat housing...has a 2 sometimes 3 wire plug

I'm not sure I completely understand your question, if youre wiring the cooling fan directly to power (with the fusible link) you'll be bypassing the PCM's output to the fan relay...the PCM uses the Coolant temp sensor (CTS) as an input to determine when to turn the fan on.

if the coolant level is going down you may have an intake or head gasket leaking coolant into the cylinders pressure test the coolant system

Here it a pic of the CTS for the computercoolant temp sensor



(1) EVAP Canister Purge Solenoid
(2) Fuel Pulse Dampener
(3) Fuel Rail with Injectors
(4) Crankcase Vent
(5) Left Bank Ignition Coils/Modules
(6) Left Bank HO2S Sensor 1
(7) Engine Coolant Temperature (ECT) Sensor
(8) Fuel Pressure Gauge Test Connector
(9) Throttle Position (TP) Sensor
(10) Idle Air Control (IAC)
hope it helps if you need more info just ask!dont forget to vote on the answer thanks have a good day DB

P0125 sets when engine coolant temp does not reach temperature for closed loop operation within a set amount of time.
May be a faulty sensor or thermostat.
P0420 Is related to a faulty rear 02sensor.
P1518 PCM & TAC module communication detected missing or invalid serial data.
If TAC related repair has been done, clear DTC & recheck system. It may be necessary to preform clear codes function twice to clear this DTC.
make sure starting system & charging system are functioning properly. Low voltage can cause this DTC to set. This should help. Let me know how its going.

Change the coolant sensor, they are faily cheap and usually easy to get to. They are also prone to failure on the early years of fuel injection.

Coolant temperature sensor is located on the intake manifold, close to the thermostat housing for the 3.4 liter and on the passenger side head for the V8's. Good luck and keep me posted.

3 things to check, 1st, temp switch (controls turning fan on and off according to eng. temp, 2. cooling fan control, tells switch when to turn on and off, and 3. fan motor. Check it to make sure it isn't shot.

on right side of engine between valvle cover and intake (#8)

1. Turn OFF the ignition.
2. Raise the vehicle. Refer to Lifting and Jacking the Vehicle.
3. Drain the engine coolant below the level of the ECT sensor. Refer to Draining and Filling Cooling System in Cooling System.
4. Lower the vehicle.
5. Disconnect the electrical connector from the ECT sensor