1998 AUDI A4 APB Engine Ignition System Checking

28-50
If all the test results so far have been OK but a
malfunction related to the camshaft position
sensor (Hall sensor) is displayed again after
erasing the DTC memory as a test measure, the
following might be the cause:

- Rotor ring (trigger wheel) for camshaft position
sensor (Hall sensor) misaligned; test phase
position.

Checking phase position of Hall sensor

- Connect vehicle diagnostic, testing and
information system VAS5051 or VAG1551 scan
tool and select engine electronics control
module by entering address word "01" Page
01
-9 . When doing this the engine must be
idling.
Rapid data transfer
HELP
Select function XX

Indicated on display
- Press buttons -0- and -8- to select function "Read Measuring Value
Block" and confirm entry with -Q- button.
Read Measurin
g Value Block
Input displa
y group number XXX

Indicated on display:
- Press buttons -0-, -9- and -3- to select "Display Group 093" and
confirm entry with -Q- button.
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28-51

Read Measuring Value Block 93
1
2
3
4

Indicated on display
- Check specified display values for Hall sensors.

Display fields

1 2 3 4
Display Group 093: Phase positions of Hall sensors (Bank 1 and Bank 2) with engine idling
Display xxx RPM xx %
0 6 KW
0 6 KW
Indicates Engine
speed
(RPM) Engine
load Phase position
Bank 1 Phase position
Bank 2
Work
range min.: 750
RPM
max.: 6800
RPM min.: 15
%
max.:
175 % -20.3 to 14.8 KW
-20.3 to 14.8 KW
Specified
value 750 - 850
RPM
0 6 KW
0 6 KW
Note
If readouts do not match specifications, unbolt Hall sensor and check whether
rotor ring is properly mounted on camshaft. If it is incorrectly mounted, the
locating lug will be flattened when the securing bolt is tightened. Also check
valve timing.
Repair Manual, 2.7 Liter V6 5V BiTurbo Engine Mechanical, Engine Code(s): APB,
Repair Group 13, Crankcase ventilation, Ribbed belt removing and installing, Timing belt removing and installing

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Misfire recognition, checking


Test sequence

- Connect vehicle diagnostic, testing and
information system VAS5051 or VAG1551 scan
tool and select engine electronics control
module by entering address word "01" Page
01
-9 . When doing this the engine must be at
idle.
Rapid data transfer
HELP
Select function XX

Indicated on display
- Press buttons -0- and -8- to select function "Read Measuring Value
Block" and confirm entry with -Q- button.
Read Measurin
g Value Block
Input displa
y group number XXX

Indicated on display
- Press buttons -0-, -1- and -4- to select "Display Group 014" and
confirm entry with -Q- button.
Read Measuring Value Block 14
1
2
3
4

Indicated on display
- Check misfire recognition.
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Display fields

1 2 3 4
Display Group 014: Misfire recognition
Display xxx / RPM xxx %
xxx
---
Indicated Engine speed
(RPM) Load
Sum of misfire
Misfire
recognition
Work range min.: 750 /
RPM
max.:
6800 /RPM min.: 0
max.:
100
activated
locked
Specified
value 650 - 720 /
RPM 15.0 -
22.0 % 0 - 15
activated
Note --- ---
If specified value is not reached: Evaluation display field
3 Page 28
-54
see also page Page 28
-55

---
If specified value is reached:

-
Press button.Rapid Data Transfer
HELP
Select function XX

Indicated on display (select function)
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Evaluation display group 014, display field 3 Display field:
3
Possible cause
Corrective action
greater 15

Spark plug faulty
Spark plug connector faulty
Ignition coil or power output stage faulty- Check spark plug and ignition cable with
connector
- Check ignition coil Page 28
-5 .
- Check power output stages Page 28
-11


Fuel injector faulty
Check compression of one or more cylinder
weak - Check fuel injectors Page 24
-39
- Check compression pressure
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The following measuring value blocks display misfiring of individual cylinders:

Display fields

1 2 3 4
Display Group 015: Misfire recognition from cylinder 1, 2 and 3
Display
xxx
xxx
xxx
---
Indicates
Amount of
misfires
cylinder 1 Amount of
misfires
cylinder 2 Amount of misfires
cylinder 3 Misfire
recognition
Work range

activated
locked
Specified
value 0...15
0...15
0...15 activated
Note
If specification is obtained: Evaluation
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Display fields

1 2 3 4
Display Group 015: Misfire recognition from cylinder 4, 5 and 6
Display
xxx
xxx
xxx
---
Indicates
Amount of
misfires
cylinder 4 Amount of
misfires
cylinder 5 Amount of misfires
cylinder 6 Misfire
recognition
Work range

activated
locked
Specified
value 0...15
0...15
0...15 activated
Note
If specification is obtained: Evaluation
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Evaluation display groups 015 and 016 Display field: 1,2 and 3 from measuring
value block 15 and 16
Possible cause
Corrective action
greater 15
Spark plug faultySpark plug connector faulty Ignition coil or power output stage
faulty - Check spark plug and ignition
cable with connector
- Check ignition coil Page 28
-5 .
- Check power output stages
Page 28
-11


Fuel injector faultyCheck compression of one or
more cylinder weak - Check fuel injectors Page 24
-39
- Check compression pressure
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