First off they didn't even make a 2003 Kia Sportage yeah I know alot about cars especially Kia itself.
Trouble code P0128 means:Coolant thermostat (coolant temp below thermostat regulating temp)
P0128 is thermostat malfunction. The thermostat needs replaced.
Trouble code P0128 means:Coolant thermostat (coolant temperature below threshold regulatin temperature)
Trouble code P0128 means:Coolant thermostat (coolant temp below thermostat regulating temp)
Trouble code P0128 means:Coolant thermostat (coolant temp below thermostat regulating temp)
Trouble code P0128 means:Coolant thermostat (coolant temp below thermostat regulating temp)
I think you meant P0128, which is a thermostat malfunction.
"COOLANT THERMOSTAT" -COOLANT TEMP BELOW THERMOSTAT TEMPERATURE
Coolant Temp below thermostat regulating temp.
Engine coolant Sensor is bad. I have the same error on my 2005.
p0128-- coolant temperature below thermotat regulating temperature---change thermostat first, and make sure coolant is ok!! then if it does not work. change coolant temperature sensor.
Coolant not reaching temp required. Usually it's sign of bad thermostat.