spark plugs AUDI A8 1998 D2 / 1.G ATQ Engine Ignition System Checking Workshop Manual

28-3
Technical data, ignition

Engine identification
ATQ (2.8 L / 5V/ 147 kW-engine)
Idle speed
Engine speed cannot be adjusted, it is regulated by idle stabilization 720 to 820 RPM (front wheel drive)
630 to 730 RPM (all wheel drive)
Engine speed (RPM) limitation
via fuel injector shut-off
about 6800 RPM
Ignition timing is determined in the control module
It is not possible to adjust the ignition timing
Ignition system Dual-spark ignition system with three ignition coils
Spark plugs Tightening torque 30 Nm.
Firing sequence 1-4-3-6-2-5
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28-8
Component location Overview of Component
Locations, page Page 24
-5

Notes:

Ignition coils and power output stage are a
common part.
Primary resistance of ignition coils cannot be
measured.
Secondary resistance must first be measured
with the ignition wires connected to the ignition
coils via the spark plug connectors of the
corresponding cylinder (This measurement will
include measurement of the shielded
resistances of the ignition wires).

- Disconnect 5-pin connector from ignition coils.

Check ignition coils (-N-, -N128- and -N158-)

- Pull the ignition wires from the spark plugs.

- In order to perform a resistance measurement, connect multimeter
between both spark plug connectors of the respective ignition circuit to
be checked.

Specification: each 16 to 27 k
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28-56
Evaluation display group 014, display field 3 and display group 015 and 016, display fields 1, 2 and 3
Indicated on
display
Possible cause
Corrective action
greater than 15

spark plug defective
spark plug connector defective
Ignition coil or power output stage faulty- Check spark plugs and ignition wires with connectors.
- Check ignition coils and power output stages Page
28
-7


Fuel injector faulty- Check fuel injectors Page 24
-36


Poor compression of one or more
cylinders
Repair Manual, Engine Mechanical, Repair Group
15 - Check compression pressure:
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