FUEL DELIVERY SYSTEM – V8 (page 4 of 6)

FUEL DELIVERY SYSTEM – V8

DESCRIPTION AND OPERATION 19-2-11

Phase 2 - Leak Detection

1 Throttle plate
2 Air flow to engine
3 Purge valve
4 Charcoal canister
5 Fuel tank
6 Tank leakage detection module

7 Air intake
8 Air filter
9 Change over valve

10 Pump
11 Reference orifice

The ECM energizes the Change Over Valve allowing the pressurized air to enter the fuel system 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 canister trapping hydrocarbon vapour and venting air 
to atmosphere through the filter.

M

M19 3580

0.5mm

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