2008 Toyota Sienna with Heat problems

Thanks! I will check the coolant. The local mechanic wasn't sure what the problem was so I went to the dealer. I am hoping someone else had run into the same problem and had a solution.

Hi, I also bought 2008 sienna 3 weeks before, it's heating is not working, radiator, thermostat changed, heater core and pipes flashed, after that heater was good just for 2 days, after that first hot air finished and than engine becoming heatup

I had the same problem. Mechanic found that the coolant was down about 1 gallon. It must have been a very slow leak as it was not noticed - no puddle in the parking place. He noted that the heat is created at the top of the system. So, if the fluid is down that much it might not effectively heat. He topped it off and the heat worked right away when I drove it home on a cold winter day just last week - in Minnesota.