1997 sl2 inside heater barely heats

There you go you answered your own question, The KIA has two cooling fans usually and if not it runs with a/c on always and when the temp reaches a certain point the fan comes on again. That vehicle caries a high relay and a low relay located in the relay box under the hood owners manual should tell you which is what.

You can replace the thermostat...it is relativity inexpensive to do..you will lose some of the antifreeze from tne top of your engine due the thermostat being a little lower then the top of the radiator..HOWEVER....Having a GM truck I believe that you have two separate problems...one the heat not coming on properly..your inside the car heat system works by sensors and activation mechanisms that work/move the doors within the heat/cooling housing..The common problem is the activater that moves from heat to cool visa/versa is defective or tne inside door is not operating properly...the activater is not to much of a job just above the gas pedal on the end of the heat/cooling housing..the other..door is on tne inside and quite a job to get at...The other gauge problem,if more the one of the gauges are fluctuating it is your computer board electrical system powering the gauge cluster..A COMMON PROBLEM ON GM AND CHEVY TRUCKS AND VANS..they can be re-calibrated but must be removed...if only the heat gauge...it may be your heat sensor on the engine block..again not a hard or expensive job..but is an important sensor..it controls the the fans that cool the engine and senses the temp of the water going to your heater core...A defective one could be sending false readings to your inside heat sensors in the cab..I.E heat not coming on right..my first bet would be CHANGE THE HEAT SENSOR.. Then go from there.Hope this helps..good luck

Have you changed your thermostat from a summer to a winter heat range?

Check the actuator motor on the heater and make sure the heater doors are fully opening and closing to direct the heat or ac. It is inside on the heater box in the end close to the driver side.

Very easy. Follow the top hose from the radiator to the engine. The Tstat is under the flange at the end of the hose. Two 8mm torx fasteners holds it down. Remove the flange, take out the old thermostat and relpace with a new thermostat and gasket. Refit flange and top up coolant. You will have lost very little because the unit is so high up. Do this while the engine is cold of course.

The heater core might need back flushed, I just did mine this winter. Go to dakota-durango.com and introduce your self and your rare as ever truck, a v6 durango, and have fun.

your radiator could be getting stopped up. also water pump could be weak. during summer though you have electric fans that should be working. need to check. you can purchase some stuff called water wetter by redline racing oil that will drop water temp 20 degrees which is substantial when a thermostat is usually 180 to 190 and boiling is 212.

Hi Phyllis, it sounds like your thermostat is stuck open, which results in the engine not being able to maintain operating temperature. This would explain the lack of heat. For your car to run at peak efficiency, u need to replace the thermostat, and enjoy having heat again!

you may have a vacum leak under the hood or dash. you may find this usually isnt that hard to fix. also look under the dash and try to find the blend door. move it to heat with your hand and see if you have heat then. good luck .

If replacing the thermostat dosen't work ,It is most likley the heater core.Don't worry it's not as bad as you think.You will need to flush it out.Disconnect the hoses from the firewall, in the engine compartment.You will find them to the left of the brake booster.A 5/8" garden hose will fit with the end cut off.You may want to place a length of hose on the opposite tube as well.Turn on the water and flush it for a few minutes.Reverse the water into the other hose to back flush.Reconnect the hoses and you should have heat.