Filter is blocking airflow. Put a new filter in a vacuum and it sounds like it's blocking airflow, not suction. I installed the old filter and it works perfectly. The new foam filter does not let air through. This is a terrible replacement filter.
Pros
SIMPLE AND EASY TO INSTALL: Replace in less than five (5) minutes, save time. Get back to daily activities quickly. Just remove the old and dirty ones and replace them. This easy to install, replaceable foam and felt filter protects your Shark from airborne or waterborne debris. When picking up liquids, dirt particles can get into the motor, which will shorten the life of your vacuum cleaner. This foam and felt filter prevents this.