warning AUDI A8 1998 D2 / 1.G ATQ Engine Motronic Injection System Servicing Workshop Manual

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Motronic injection system,
servicing

Safety precautions

If special testing equipment is required during
road test, note the following:

WARNING!

Scan tools and testing devices must always
be secured on the rear seat and operated
from there by a second person.
If a scan tool or testing device were to be
operated from the passenger seat and there
were an accident involving activation of the
passenger-side airbag, the person seated
there could be seriously injured.
To reduce the risk of personal injury and/or
damage to the fuel injection and ignition system,
always observe the following:
Only disconnect and reconnect wires for
injection and ignition system, including test
leads, when ignition is turned off.
If engine is to be cranked at starting RPM
without starting (e.g. for compression testing),
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It is possible that the control module will
recognize a malfunction and store a DTC during
some tests. After completing all tests and
repairs, DTC memory should therefore be
checked and erased if necessary. Readiness
code must be generated after DTC memory is
erased Page 01
-82
.

Always switch ignition off before cleaning
engine.
The battery should only be disconnected and
reconnected when the ignition is turned off,
since otherwise the Engine Control Module
(ECM) can be damaged.

WARNING!

Fuel system is under pressure! Place a cloth
around the connection point before opening
system. Then release pressure by carefully
loosening connection point.
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24-31

WARNING!

Fuel system is under pressure! Place a cloth
around the connection point before opening
system. Then release pressure by carefully
loosening connection point.

Checking system pressure - Remove engine cover (arrows).

Note:
If fuel should escape at the vacuum connection of the pressure regulator
during the following pressure test, replace pressure regulator. - Connect VAG1318 pressure gauge using adapters
VAG1318/7, /1318/8 pressure hose with connectors and 1318/15
adapter in supply line.
- Disconnect vacuum hose from pressure regulator to intake manifold at
pressure regulator and seal line.
- Start engine and let run at idle.
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Fuel injectors, removing and installing


- Remove engine cover (arrows).
- Remove intake air hose between Mass Air Flow (MAF) sensor and
intake air elbow.
- Remove all harness connectors to injectors.
- Disconnect vacuum hose from fuel pressure regulator.
- Expose wires at fuel distributor.

WARNING!
Fuel system is under pressure! Place a cloth around the connection
point before opening system. Then release pressure by carefully
loosening connection point. - Unscrew fuel distributor from intake manifold (arrows) .
- Remove fuel distributor with injectors from intake manifold
simultaneously upward and set aside in rear of engine compartment on
a clean cloth.
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