Question about 2003 BMW 325

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Sour Vinager odor in vents when using AC in a 2003 325i???

The strong smell does not appear when using the heater. I have to open the windows and run the ac full blast to clear the smell before being able to remain in the car. Our dealer in MD told us to turn off the ac about a mile from home and run the fan at full speed to clear the vents????? A technician in NC who I happened to meet told me to replace a filter that is on the hood and there is also a spray we can spray into the system to attempt to clean the mold and whatever is bldg up in there. So, my question to you is - what can we do and have you encountered this issue before.

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Milk may have been split in the vents
it goes very sour & vandals sometimes do it on the street!

Posted on Jul 20, 2009


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