guMBy

Lately, on several occasions I have noticed a strange smell in my car. It is not very strong and seems like it is coming from the dashboard vents. It smells a bit like caramel or butterscotch. I am thinking it may have something to do with the heater core having a very small leak and what I am smelling is coolant. The funny thing is that the first time I noticed it was the day after I ate a bunch of toffees while driving. I searched under the seats for one that may have escaped, or a wrapper, but found none. I don't always smell it and just know that if I bring it to the dealer, it will be a no smell day. Anyone had a heater core leak cause this smell?

GLKpaul

I've had a heater core leak albeit not in my MB, it does tend to have a sweetish smell. I would do a little hunting see if there are signs of a leak, and check/watch the coolant level it should go down. Put the heater on hi when its hot see if you can make it smell.

If you figure out how to bottle the toffee/caramel smell - i'll buy it

Marek_Norway

If you noticed also thin greasy coating on windshield, it is deffinitely coolant leak. Try also clean airconditioning...

GLKpaul

I would also check your cabin filter, easy and it may hold some secrets...

guMBy

Well, it seems the smell is only really noticeable when the heat is on and the fan is on low. No smell with aircon that I can tell. It's almost like someone dropped a old, wet butter rum lifesaver in the air vent. I still think it is a really slow sweat type leak in the heater core or hose. There doesn't seem to be any film on the inside of the windshield other than the standard crud that is always on there. I will have to check the cabin filter. That is a good idea, I would have never thought of that.