2006 Jeep Liberty Troubleshooting Overheating Issues

[sfmedic200]

I have a 2006 Jeep Liberty 2wd (V6-3.7L) with 150k miles that has been overheating on the dashboard temperature gauge for the past few weeks. I have replaced the radiator, water pump, thermostat, and the sensor for the temperature gauge.

The vehicle does not actually seem to be overheating (no bubbling when cold, no smoke, both rubber hoses to and from radiator get warm and feel like coolant is running through them, etc...). The fan turns on just fine and the a/c and heater work. The vehicle still reads on that gauge as overheating though and it occurs when driving on the highway or stopped at a light. It takes about 10 minutes for the car to warm up and as soon as it does, the gauge starts to go up. When I turn the heater on full blast, the gauge will start to go down. This is no fun in the Texas heat, so I am looking for another solution.

The serpentine belt looks good and the oil looks good (changed Saturday). There are also no coolant leaks and the car does not use a lot of coolant.

Is it just a short in a wire causing the gauge to read hot? Should I start worrying about a head gasket? Is it just the relay or a fuse? Should I replace the fan even though it is working? Any ideas are appreciated as this is my first JEEP.

[2000izusu]

do a combustion test on the antifreeze. kits are available at auto store