In my chevy impala i have no hot air comming out of the vents. The temperture gage reads at about half and then will fluctuate. What could be the problem?

If the coolant level is low in the engine it can cause heat fluctuations from the heater, as well as an incorrect reading on the gauge. Make sure the coolant level is correct in the engine.

Bleed the air out of the system

If its the 3.1 or 3.4 they almost always leak under the intake where the intake touches the engine block..Sometimes they even leak internally and could get in your oil..You really need to pressurized the cooling sytem to know exactly wheres its coming from..Sometimes if leaks are small they can hit hot parts of the engine and burn off before you can catch it..So if you use a pressure checker youll be able to find it..I would try autozone they have some tools you can rent for free just leave a deposit

It sounds like you may have a stuck thermostat or a water pump with deteriorated cooling fins. Also did you burp the system properly?

this problem is caused by a sticking air temperature control blend door actuator or blend door, this door moves back and forth to get the desired temp, the actuator is electronic and prone to this type of problem, suggest u replace it.

sounds like the gauge and sensor r workin properly....but you do have to address that coolant leak...that causes your temp to fluctuate cuz you cooling capacity is being reduced

Hey,

I just replaced my thermostat in my car due to the same problem. Except mine was a 92. I figured I'd start with the thermostat and antifreeze. Then the heating core. Now I have heat.

But yet I still have no heat on the windshield.

replace right temp door actuator under passenger side of instrument panel

. make sure valve on hose to heater from radiator is all the way open.

My Name Is Phil Call Me And Give Me More Details 870-718-8850