With the car at normal operating temperature, the heat is on the highest setting it will not blow as hot as it should. At higher rpms the heat blows a little hotter. Is this a clogged heater core? Thanks
My car has 88459miles.
My car has a manual transmission.
A clogged heater core is a possibility. The other possibilities that should be considered are a faulty heater control valve, malfunctioning blend door(s) in the in-dash ventilation network, collapsed hoses, inadequate coolant, and trapped air in the cooling system. If the engine operating temperature is normal, the thermostat would not be implicated. The recommended service to identify the fault is a no heat diagnostic. At the conclusion of that diagnostic and inspection, the certified mechanic would explain the required repair and provide you with an estimate.