Evaporative Emissions System: Description and Operation

Purge System Control
- The purge control system on the M44 engine has been modified to allow it to comply with TLEV standards. Purge control and monitoring are control functions of the M5.2 management system.

The system is redesigned and matches the purge control system found on the E36 - 328i. The components of the M44 purge system include:
^ Charcoal canister with integrated shut off valve
^ Evaporative purge valve
^ Fuel tank pressure sensor
^ Liquid vapor separator
^ Vehicle fuel tank
^ M5.2 control module

- The charcoal canister is 3.0 liters in size and its installed location is in the trunk, under the spare tire. The larger canister allows for the containment of more HC vapors with less escape to the atmosphere. Vapors that accumulate in the canister are allowed to pass through the liquid/vapor separator and condense back into the fuel tank.