Ive been noticing lately that my temp is always below normal, sometimes barely even moving a notch? This wouldnt be the thermo would it? Ive replaced it during the summer. Its always been in the middle between cold and hot. Any advice?

 

It could be a bad thermostat, but it could also be the coolant temperature sensor. Does the gauge kind of "have a mind of it's own" or does it stay in one spot? Oh, and have you checked to see if your upper radiator hose is getting hot? If it isn't, then your thermostat is bad.

 

If the car will blow heat after sitting still but the heat cools when you start driving, your thermostat is bad. If the gauge reads cold but you get heat while driving it's the sensor.

 

I replaced my CTS with one from NAPA, it wasnt long after I had the exact problems you describe so I ended up replacing it again with one from ECS.

 

im having the same issue, and now its overheating...i think i may have air in my system..