2003 MDX no heat
 

Good evening
I have a 2003 acura MDX and just can't seem to find the problem.
it is only throwing luke warm air and in our brutally cold winters that luke warm air feels more like cool breeze.
I did a complete heater core flush as well as a radiator flush.
Installed new thermostat.
Fresh OEM coolent.
I checked the heater water valve by the firewall and it moves correctly.
I checked the vent position motor which works good too
I also checked the air mix motor which also works good.
The car itself runs great and doesn't over heat, comes up normally to operating temp. The system has lots of pressure.
the ac works good too, and the blower motor is functioning strong. I just can't get hot air

have you burped the radiator to ensure there's no air in it?

I just had the cap off and ran the car twice to operating temperature. If that's what u mean by burping.

right after doing the flushes and the thermostat the car was throwing super hot air,I had it test running for about 1h. I drove it for about 45min afterwards to the owners house and was giving great air, handed the car over and then the customer drove it and apparently 10min he started driving the temperature went from hot to Luke warm again. Since then I tested all other co.ponents but haven't been able to get the air hot again

Made something similar work, done it but the coolent level did not move anymore. Rad is full and the over flow level is also good