it is not a thermostat problem is an actuator located under the dash that lets the water pass through the heater core, all these cars got the same problem dude good luck...
Possible the thermostat installed upside down. Spring goes toward engine. Also may be air in the system. Bleed the cooling system with the heater set to hot. The heater core may also be stopped up.
heating element stopped working
could be the timing belt
A clogged fuel filter can cause a Mitsubishi Galant to idle rough for the first 10 minutes it is running and then it runs fine after that. A fouled spark plug can also cause this issue.
Thermostat, or fan motor if it does not blow hard.
There are several things that can cause your 2003 Mitsubishi Gallant speedometer not to work. The most common cause is a malfunctioning speedometer cable.
Yes, it sure can.
the door lock actuator is bad. it is located in the drivers door panel
The actual removal of the thermostat will not cause this condition but if you possibly disconnected a vacuum hose white changing the thermostat, WOULD cause that problem. Check all of the vacuum hoses to make sure they are connected and tight.
Thermostat would be my first guess, If not is a fan blown, do a radiator flush?
ECM will not cause A/C to not work properly. some of the earlier mitsubishi's had a ground wire for the A/C going through the ECM. and i have ran into the circuit in the ECM that grounds it go out causing the A/C to not work on a few diffrent cars
Look to see if you threw a fan belt. Check your thermostat. That is the most likely cause. Then check your water pump.
this is caused by the sensor tripping in the light sensor to see what causes this you must diagnose it with a computer and see what fails in it.