Fuel System, Checking For Leaks
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Leak Detection System
- The function of the leak detection system is based on the premise that the fuel systems creates a natural vacuum when the fuel in the fuel tank becomes colder.
- For the leak detection the temperature and pressure measuring devices are needed. The Fuel Tank Leak Detection Control Module -J909- item -2- with an integrated Fuel Tank Pressure Sensor -G400- located on the EVAP canister -7- supplies these values.
- The system is considered to be closed when the measured vacuum is 2.5 mbar (1.87 mmHg) as the fuel tank temperature drops.
- There is a leak in the fuel system if there is not vacuum, which will result as an entry in the control module DTC memory.
1 - Signal wire to the Engine Control Module -J623-
3 - Bleed line to the engine
4 - Fuel tank
5 - Fuel tank vent line
6 - Air filter vent line