Fuel & ignition

Fuel-vapor charcoal canister

Temporarily traps fuel vapor for later controlled burning.

Where it sits

Near the fuel tank or rear underbody on equipped petrol cars.

How it works

Activated carbon adsorbs vapor; controlled airflow later carries vapor toward the engine.

Think of it as

An odor-trapping storage sponge.

Symptoms when it fails

Fuel smell or evaporative-system faults can involve the canister, seals, valves or plumbing.

Lifespan

Plugs and filters use engine-specific service guidance. Pumps and injectors are normally assessed through pressure, leakage and electrical tests.

Repair cost

Spark-plug service is usually less involved than direct-injector or high-pressure-pump replacement; coding and access can add work.

The BMW angle

A BMW vapor canister handles fuel vapor; it is not an exhaust particulate filter.

Used in

BMW combustion models; spark components are petrol-only and glow-plug hardware is diesel-only.

Sources
Same system

Fuel & ignition