Temp gauge often reads too hot, engine normal.

Hi Bill, is the engine actually getting hot enough for the fans to come on? if the engine does have overheating problem (but you say the temp gauge reads normal) then i would check the operation of the engine temp switch, there are two, one for the gauge and one for the fans.

providing your coolant is full cause low coolant will cause no heat
and your temp gauge is normal in the middle then most likely u have a bad blend door actuator usually on the passenger side

Is the temperature gauge reading about 210 degrees? If the temp is low, the thermostat may be stuck open and not allowing sufficient heat. Also check the heater hoses to see if they are hot to the touch. If one feels hot and the other is cold or only warm, heater core is becoming clogged.

There is a blower control resistor (manual system) or a blower transistor (automatic temp system) located behind the glove compartment in the HVAC box and this is a high failure item.

Sounds Like A Problem With your thermostat. Good Luck

heat sensor for radiator fan switch, thermistat,water pump? Does hot air blow when moving? does car over heat when sitting idling for over 10 minutes. If so check fan first, then water pump. last cause thermisat

the climate unit has an internal fault

I think you could be right about there being air trapped in the system.
Or the heater core(radiator) is plugged.
Either way you need a pressurized radiator coolant pump to put the coolant in without air being trapped.
Although,i have seen it done by jacking the vehicle up high enough that the radiator was now higher than the heater core level, and then the coolant was put in.
But this is dangerous to try.

Check to make sure your thermostat works right by monitoring the warming up of your engine. With a completely cold engine, start and run the engine for a few minutes, then put your hand on the top radiator hose to monitor if and when it gets warm as the thermostat opens more and more and note the gauge reading( if it works) the top radiator hose should be unbearably hot within 5-8 minutes. If the therm. opens right it should close right aswell, staying open a little while eventhough the radiator may have cooled may be what you are experiencing causing the rapid cooling and is nothing to worry about. The Hose should not get warm very soon after starting the engine. Regarding you gauge, lets take one step at a time, verify proper op. or the therm.

It may be the thermostat