The Intex pool pump uses a filter cartridge, which you need to clean weekly or daily depending on the amount of use the pool gets during the week. The filter cartridge cleans the water and traps debris as the water filters from the pool to the pump and back to the pool. When the accordion-styled filter is dirty, the pump has a hard time pumping the water. You will need to clean and replace the filter when cleaning doesn't work.
Turn off the Intex pool pump. Disconnect the the top hose's strainer grid, which brings the water from the pool to the filter, and disconnect the inlet nozzle on the bottom hose, which is where the water flows back to the pool.
Turn the threaded collar on the pump counterclockwise to remove the cover from the pump. Carefully remove the cover seal, which looks like a big O-ring.
Pull up on the filter cartridge to remove it from the pump housing.
Use the garden hose with a spray nozzle to spray the filter and remove the debris. If the filter is not catching the debris or looks worn, replace the filter with a new one.
Place the clean or new filter back in the pump housing. Place the cover seal on the housing. Place the threaded cover on the housing and turn clockwise to tighten.
Open the air release valve on the top of the cover to release air from inside of the pump. Wait for the air to stop hissing out. Close the air valve release. Replace the inlet nozzle on the bottom hose and the strainer grid on the top hose. Turn on the pump.