Toyota Repair: Heater and burning smell, mile warranty, something burning

Question
We have a 2002 Sienna.  When the heater is on and the air flow is directed to the floor or defroster we smell a strong odor of something burning or like a hot metal smell.  Any suggestions on what is causing this?  We have had no prior problems with the vehicle.

Answer
Check the exhaust system to see if any plastic bags etc., may have been picked up on the road and melted to the pipes or muffler, if there is nothing obvious I recommend taking it into the dealer, whatever the problem is it may be covered under the 3yr/36,000 mile warranty.