Air & turbo

Air-filter housing

Holds the air filter and directs clean air into the intake.

Where it sits

In the engine bay connected to the intake duct.

How it works

The housing locates the filter seal and can include resonators or airflow-sensor mounting points.

Think of it as

A sealed case around the engine’s dust mask.

Symptoms when it fails

Cracks or loose clips can admit unfiltered air or create intake noise.

Lifespan

Filters follow the vehicle service schedule; ducts and boost hardware are inspected for condition, sealing and operation.

Repair cost

A hose or filter is generally simpler to service than a turbo assembly. Access and diagnosis can dominate cost.

The BMW angle

BMW airbox layouts vary with the engine and available space, even within one model generation.

Used in

BMW combustion models; boost hardware applies to turbocharged engines only.

Sources
Same system

Air & turbo

Engine air filterRemoves dust from air before it enters the engine.Intake manifoldDistributes incoming air to the cylinders.Throttle bodyUses a movable plate to regulate an intake passage.TurbochargerUses exhaust energy to push more air into the engine.Turbo wastegateDiverts exhaust around the turbine to help control boost.Turbo diverter valveRelieves compressed intake air when operating conditions call for it.Charge-air coolerRemoves heat from compressed intake air.Charge pipeCarries pressurized air from the turbo toward the engine.