1999 kia sportage overheating

Did you bleed your system of air???....usually a bleed screw near the thermostat housing...get allllll the air out...simetimes the heater core is at the highest oart if the system..therefore if there is air in system..thats where the air settles and no coolant will flow through the heater cire!!

Did you change the thermostat,flush the radiator?Check the cooling fans if they are working.

sounds like your thermostat is either stuck or broken

for the overheating start by flushing the cooling system then try the thermostat and if that dont do change waterpump

Rusty is from running a bad or no mix of coolant. (PH level is off) You may have a water pump that has corroded impellers, and can't move the coolant as well any more. I would start by making sure to flush the engine block again, and make sure you flush water through every possible hose, and where you can get at it.

The thermostat is the engine temp controller. All the sensors do is relay information.

Are you sure your over heating. Has anyone infrared temp tested the actual temperature.

If you are really overheating a temp gun can test differnnt areas to try to find a blockage somewhere.

You could have a clogged radiator if you used a sealer in the coolant pryor to doing the head gasket.

You have to install a new Thermostat because if the motor has no water pump thermostat sends all the coolant to the radiator and therefore the engine never warmed and you will not have heat because the coolant never be heated

while your car is running and, warmed up; squeeze the top radiator hose; if you feel coolant flowing your thermostat is open and your waterpump is working if your waterpump fails it usually drips coolant out of a "weep" hole on to the ground first.

check fuse and relay for fan switch. replace both if needed. real cheap fix.

the situation you describe is an air pocket. you need to raise the front of the vehicle turn the heat on full blast. open the radiator cap, while cold of course, and add coolant until you see not more air bubbles coming out of the filler neck.