Motor BMW 735i 1999 E38 M62TU Engine User Guide

PHASE 2 - LEAK DETECTION

The ECM energizes the Change Over Valve allowing the pressurized air to enter the fuel sys-

tem through the Charcoal Canister, The ECM monitors the current flow and compares it

with the stored reference measurement over a duration of time.

Once the test is concluded, the ECM stops the pump motor and immediately de-energizes

the change over valve. This allows the stored pressure to vent thorough the charcoal can-

ister trapping hydrocarbon vapor and venting air to atmosphere through the filter.
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