What Causes the Sour Smell When Turning on the Air Conditioning in a BMW?

1 Answers
SanLondon
07/29/25 9:38pm
The sour smell when turning on the air conditioning in a BMW is caused by a dirty air conditioning filter that has been used for too long. The functions of the air conditioning system are: 1. To cool, heat, ventilate, and purify the air inside the car; 2. To provide a comfortable environment for passengers, reduce driver fatigue, and improve driving safety. Taking the 2021 BMW 5 Series as an example, it belongs to the mid-to-large-sized car category, with body dimensions of: length 5106mm, width 1868mm, height 1500mm, wheelbase 3105mm, fuel tank capacity 68l, and curb weight 1705kg. The 2021 BMW 5 Series features a double-wishbone independent front suspension and a multi-link independent rear suspension. It is equipped with a 2.0l turbocharged engine, delivering a maximum horsepower of 184ps, maximum power of 135kw, maximum torque of 290nm, paired with an 8-speed automatic transmission.
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