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♦ Unplugged electrical connectors; keep them clean and dry.
Make sure connections are dry when attaching.
1.4 Procedure to be followed prior to open‐
ing high-pressure injection system - take
note of the following:
Caution
The injection system consists of a high-pressure section
(maximum approx. 120 bar) and a low-pressure section (ap‐
prox. 6 bar).
Prior to opening the high-pressure section (e.g. when re‐
moving the high-pressure pump, fuel rail, injectors, fuel pipes
or fuel pressure sender -G247- , the fuel pressure in the high-
pressure section must be reduced to a residual pressure of
approx. 6 bar. The appropriate procedure is described below.
Reducing fuel pressure in high-pressure section
– Detach electrical connector at fuel pressure regulating valve -
N276- -2- .
– Allow engine to idle for about 10 seconds.
Note
♦
Fuel pressure will be reduced from approx. 50 bar to approx.
6 bar when electrical connector is detached from fuel pressure
regulating valve -N276- while engine is idling.
– Switch off ignition.
WARNING
The fuel lines are still filled with fuel, however the fuel is no
longer under high pressure. Wear safety goggles and pro‐
tective clothing when opening the fuel system to avoid pos‐
sible injury and skin contact.
Before opening the high-pressure section, wrap a cloth
around the connection.
– The high-pressure system must be opened IMMEDIATELY
after reducing the pressure by wrapping a clean cloth around
the connection and allowing the residual pressure (approx. 6
bar) to dissipate. Any discharged fuel must be collected.
– Upon completion of repair work, interrogate fault memory of
engine control unit and erase any error entries caused by de‐
taching the electrical connector.
– Generate readiness code in engine control unit in “Guided fault
finding” mode.
Audi A3 2004 ➤
Direct petrol injection and ignition system (4-cyl. 2.0 ltr. 4-valve turbo) - Edition 11.2005
1. Servicing injection system 3
