there could be several things, dust in your heater could just be burning a little (normal! not a problem) or your heater core could be burn out and leaking fluid all over where you can't see. but don't take my word for it!
dryer sheets in the heater vents may help
the heater core, heater core hoses or heater control valve is leaking
If the heater has a sweet smell it could be that the heater core is leaking engine coolant. When the leak gets worse you will have a wet floor on the passenger side and the windshield will fog up when you turn on the defroster.
Usally the AC Drain is stoped up & there is standing water & debre in the evaperator case U need 2 take something soft & stick up through the ac drain under the hood of the vehicle,nothing sharp or U could puncture the Evaperator core.compressed air usally works good.AnswerSounds like you have a leaking heater core. The smell that you describe is the smell of eng. coolant. If you turn your heater on to full max it will get stronger. Or, a cat slept on your car and you know what that means. Cat piss. It happen to me years ago.
Might be a leaky heater core, the anti freeze in the coolant has a sweet smell/taste.
It is possible that a car can smell like gas when the heater is turned on for a few reasons. One possible reason that this happens could be a leak in the line.
Leaking heater core
dryer sheets in the heater vents may help
A burning smell from a car's brakes means that you are braking very hard or there is a electrical short circuit in the car. Another reason for a burning smell may actually be coming from the car's heater.
Heater core is probally leaking. Should be located under dash on passenger side.
Typical of the heater core leaking. Overheat because of low fluid and pressure. Foggy windshield due to heater core leaking and will smell antifreeze in the car.
if you can smell antifreeze you need to replace the heater core in the vehicle
under low temperatures, this > > equipment automatically starts and i can hear it running; the problem is > > that when i stop the car, i feel a very bed smell, ... I've noticed it occasionally, but not the smell > getting inside the car - my TiD has the ACC heater so maybe this stops > it. Do you have ACC or a manual heater
what are you driving? email me direct if you wish
It probably has a leak, possibly from the heater core.
You have a leaking heater core. You might smell antifreeze if you turn on the defroster.
You most likely have a leak or your car is overheating. If you are smelling it in the car then in all probability the heater core is leaking.