I would check to see if your A/C drain is plugged,it is located in the same area you are describing,but that warm syrup type smell is probably a heater core,and I do believe it involves removal of the dash,but no special tools(I think),get a haynes shop manual (10 $)or so,and read up before you start,it is time consuming,oh,here is one more check,checkthe wetness in your carpet to be sure its coolant,put a white towel on it and if it turns bright green its coolant