The refrigerator in my kitchen was doing something strange: lettuce would freeze on one shelf, while drinks on another shelf were barely cold enough. I had already cleaned the coils and adjusted the settings, but the airflow inside the fresh food section still felt wrong. After reading about the cold air passage between the freezer and refrigerator, I focused on the diffuser assembly. Appliance Parts 4 All had the Whirlpool refrigerator air diffuser assembly listed with the manufacturer number, and the description explained that it adjusts the passage of cold air. The part I chose was WP2216112, a Whirlpool refrigerator air diffuser assembly with a motor and shutter. That made sense because my problem was not total cooling failure, but poor air control. When the part arrived, I unplugged the refrigerator, removed the interior cover, and compared the old diffuser with the new one. The old shutter seemed sticky and inconsistent. The new assembly fit correctly, and the connector matched without any modification. After I put everything back together, I gave the refrigerator a full day to stabilize. The temperature became more even, food stopped freezing randomly, and the refrigerator finally behaved normally again.