Hey all, just asking for help and opinions.

When its about 60F or higher outside my temp gauge will reach just below the middle marker. Anything below say 50F and it will reach below that point while idling. Fan off, climate control all the way to Hot. When I start to drive or turn the fan on, the temp gauge will fall to a few ticks above cold...

Also, everytime I fill the reservoir, it'll take around 1-3 days and its empty. Or the radiator is below full. Yet there is no puddle on the ground.

I'm planning on changing the thermostat but, where could I be losing the coolant? Headgasket? My dipstick doesnt appear to be milky looking.

Thanks in advance.

 

I would say you're losing the fluid at the water pump if not head gasket. As far as troubleshooting temp problem, replace t-stat first since it is so cheap. Otherwise, bleed system ince air could be stuck and compresses differently at different temps under pressure.