About this part
What it does. K And N Replacement Air Filter K&N 400-33-3171 keeps dust and debris out of the intake so the engine draws clean air.
Symptoms that point to this part
- Reduced fuel economy
- Sluggish acceleration
- Visibly dirty or clogged filter element
Service note. Typically inspected at every service and replaced roughly annually.
Fitment. Catalogued as fitting 2021–2026 BMW M4, 2024–2025 BMW M2, 2021–2024 BMW M3. Engine, sub-model and trim can narrow fitment further, so check those attributes on the listing before ordering.