I recently picked up 2011 mini cooper s with 77.5k miles and ac and heater smell rubbing alcohol.. I installed a new cabin air filter but still smells same..I don't see any coolant leak.. could it be heater core?

 

So the two things I could think of are the heater core leaking coolant, or maybe windshield washer fluid getting into the system (like if it's running under/down the trim onto the cabin air filter). Maybe try smelling the coolant (car cold) and washer fluid to see if the smell resembles either of those? I'm not familiar enough with the R56 HVAC system to know where you'd check for heater core leaks, sorry.

It's also possible someone sprayed HVAC system cleaner into the vents and intake and you're smelling the residue of that. If you've got a musty smell there are various alcohol-based sprays that are used to clean that up. If that's the case just running it on high for a while should clean it out.

 

Thanks for the reply! I've been checking the coolant level in coolant reservoir but I don't see any reduces (I checked everyday pretty much) and I don't smell anything sweet inside the car and the carpet is dry.

 

It could just be residue from some "heavy duty cleaning product" that the previous owner (or car lot) used. Some products used to mask cigarette odor have a chemical smell (better than an ashtray, but...).