The engine oil filter is designed to protect and capture harmful contaminants like carbon, sand, dust, and bits of metal that circulate into your engine. It filters the oil to prolong its life and to provide long lasting engine protection. It is important to have clean motor oil because dirty oil can wear the oil pump’s machined components and damage the bearing surfaces in the engine. The oil filter helps remove pollutants from your car engine’s oil that can accumulate over time.