03 Z4 2.5L, 170k miles With temp knob at max heat car blows lukewarm warm air out footwell and cool air out upper vents. Fan working normal. Recently replaced water pump, expansion tank and thermostat. Car was bled by mechanic and I ensured it was topped off. Both heater hoses are firm and hot when car is at temp. No abnormal gauge readings. I'm leaning to something electrical or a jammed mixing valve. Maybe a temp sensor?