Most mass air sensors will go through its own cleaning process by periodically heating its sensor wires to burn off any contaminates. However, this is not always sufficient. Carb cleaner has been known to do the trick, but CRC now has a dedicated Mass Air Flow Sensor Cleaner that is safe for the sensor and plastic housing. I clean mine roughly once per year but I've heard of some people in dusty environments clean their meter once a month.
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