audi Workshop Repair Guides

Audi Workshop Service and Repair Manuals

Bleeding fuel system > < Overview of fitting locations
System layout
   
System layout
  Caution
Risk of malfunctions caused by dirt.
Observe → Chapter „Rules for cleanliness and instructions for working on fuel system“.
The high-pressure fuel pump has very close tolerances and must not be allowed to run without fuel. To prevent this and to enable the engine to start quickly after parts have been renewed, it is important to observe the following:
t  If components of the fuel system between the fuel tank and the high-pressure pump are removed or renewed, the fuel system must be bled → Chapter.
t  If the high-pressure pump is removed or renewed, the first fuel filling operation must be performed before the engine is started for the first time → Chapter.
  Note
The high-pressure pump will be damaged if the first fuel filling operation is not performed.
1 - Fuel metering valve -N290-
2 - High-pressure pump
q   Exploded view → Chapter „High-pressure pump - exploded view“
3 - Fuel pressure sender -G247-
q   Exploded view → Chapter „Injectors - exploded view“
4 - Fuel rail
q   Exploded view → Chapter
5 - Fuel pressure regulating valve -N276-
q   Exploded view → Chapter
6 - Injector
q   Piezo injector
q   Exploded view → Chapter
7 - Fuel return hose
q   Do not dismantle
8 - Pressure retention valve
q   Maintains a residual pressure of approx. 1 bar in fuel return hoses (for control function)
q   Cannot be renewed separately; if defective, renew fuel return hoses
9 - Fuel tank
q   With fuel system pressurisation pump -G6-
10 - Not fitted
11 - Fuel filter
q   Exploded view → Rep. gr.20

   

Bleeding fuel system > < Overview of fitting locations