
It is normal for the car's air conditioning to become louder after changing the filter. The function of the car's air conditioning filter: It ensures the filter fits tightly against the housing, preventing unfiltered air from entering the cabin. It separates solid impurities such as dust, pollen, and abrasive particles from the air. It adsorbs moisture, soot, ozone, odors, carbon oxides, SO2, CO2, etc., from the air and has strong and long-lasting moisture adsorption capabilities. Maintenance of the car's air conditioning filter: If the filter is dirty, clean it by blowing compressed air from the opposite side. Hold the air gun about 5 cm away from the filter and blow at 500 kPa pressure for approximately 2 minutes. The air conditioning filter easily accumulates dust, so blowing away loose dust with compressed air is sufficient.

Last time I replaced the cabin air filter, I also encountered this situation - the whooshing sound became noticeably louder when turning on the AC. Upon reflection, it's probably because the new filter's denser material creates stronger wind resistance, increasing the blower motor's workload. Other possibilities include not cleaning accumulated dust in the air ducts during replacement, or improper filter installation leaving gaps. When I reduced the fan speed by one level, the noise diminished significantly, indicating the blower needs to adjust its operating intensity to accommodate the new filter. I recommend monitoring it for a few days - if the noise persists, reopen and inspect the installation. When DIY filter replacement, always wear gloves to prevent oil contamination of the filter paper, as this affects the entire HVAC system's lifespan.

With over a decade of car repair experience, I've encountered many car owners complaining about increased AC noise after replacing the cabin air filter. This typically falls into three scenarios: First, the filter density doesn't match the original design, where overly dense filter material increases blower resistance; Second, improper installation causes filter frame resonance; Third, accumulated dust on the AC blower blades loosens during filter replacement. The most effective troubleshooting method is to start the AC and press on the filter cover - if the noise disappears, it indicates an installation issue. We recommend using OEM filters first, as aftermarket parts often have poor dimensional tolerance control. During replacement, remember to clean the blower fan blades with a vacuum cleaner - a detail many repair shops overlook.

As a car modification enthusiast, I've specifically tested how different AC filter materials affect noise levels. Bamboo charcoal composite filters generate more wind noise compared to ordinary non-woven filters due to their thicker adsorption layer. However, honeycomb-structured activated carbon filters can actually reduce airflow whistling. I encountered similar issues when upgrading my Civic's performance filter - later discovering it was caused by missing buffer pads between the filter frame and AC housing. Now I always apply soundproof tape to the contact surfaces during DIY installations. If noise bothers you, try installing a soft rubber airflow guide ring to redirect air currents and effectively reduce wind shear noise.


