There are all sorts of places that coolant can be leaking from. You just have to look until you locate it.
Rear of engine, underneath the exhaust manifold. you can follow the coolant line (approx. 2") tha runs underneath your engine, then runs up the back of the engine, up to the thermostat.
it is underneath the air filter housing,look for the large coolant hose
stop an engine
Water pump maybe?
The coolant thermostant is located just underneath the alternator. Follow the lower radiator hose to the engine. It comes as an assembly, Meaning the housing is built into the thermostat itself.
if u changed thermostat it has to be reset so fan can turn on correctly
If it is leaking coolant. And you changed the thermostat. I would then move to this section. Flush the radiator and the heater core. This can be done at a certified shop with a reliable mechanic.
"COOLANT THERMOSTAT" -COOLANT TEMP BELOW THERMOSTAT TEMPERATURE
Drain the radiator. Remove the top radiator hose. Remove the water inlet, and take the thermostat from underneath it. Install the new thermostat. Reinstall the inlet and hose. Fill the system with coolant.
First check the water level. Low level will not get to the heater core. Change the thermostat. If you recently changed the thermostat, bleed the coolant system.
The thermostat on a 99 Mitsubishi Galant is changed by draining the coolant, removing the upper radiator hose, and unbolting the housing. The thermostat can then be removed and a new one put into place.
flush the system and change thermostat,this should fix problem. I flushed mine and i changed coolant and thermostat,it is now fine.