Hi all:
This is my second car that has smell problem in the cabin giving me bitter taste in mouth and headache right at the first breathing in. This smell is kind of sweet (I initially thought it was air freshener) and is present even without any driving or engine idling. If I open all four doors for a while to make sure the air is fresh in the cabin, then close all doors, then 30 minutes later, the smell appears in the cabin. This means that the source of the smell is somewhere in the cabin and not in the engine compartment.
I theorized that the smell comes from a pin hole leaking heater core because the car is not losing coolant.
To test that theory, I bypassed the heater core and flowed tap water through it until the water coming out the heater core became clear. But the smell persists in the cabin.
I then theorized that some coolant having leaked out of the heater core before the flushing of the heater core remained between the fins of the heater core. But two days passed and the smell persisted.
Then, freezing temperatures returned, so I had to reconnect the heater core to the cooling system.
I regret that I did not turn on the fan/blower to max to blow air through the fins of the heater core to evaporate the leaking coolant. Next week, temperatures will go above freezing again. Then, I will test my theory of coolant reamaining between heater core fins again.
What do you think? Can the smell in the cabin come from leaking refrigerant? Or any other sources?
Thanks, Madison18