C - Checking Residual Pressure
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-- Watch the pressure fall on the :VAS6550 while checking the holding pressure and checking for leaks:
- After 10 minutes there must be a residual pressure of at least 3 bar (43 psi).
If the Residual Pressure Drops Below 3 bar (43 psi):
- Check fuel lines and their connections for leaks.
- There is a leak at the check valve in the fuel pump: Replace the fuel delivery unit. Refer to FUEL DELIVERY UNIT/FUEL LEVEL SENSOR, REMOVING AND INSTALLING .