Dash heat only blows cool air

trop-a-cal wrote:
Then there is possible low coolant which starves the heater core first due to it being at highest point in system. Always check when engine is cold and no pressure is present in lines. You may also have a mechanical inline heater valve in the hose going to the heater core that is not connected or stuck closed. That would be controlled by the dash heater lever and connected via a cable to the inline valve.

I would lean toward low coolant, especially if the engine temp never gets above 165 degrees. That by its self is a read flag that something is not right. Idle temp will be anywhere from 195 to around 205 depending on where the sensor is.