Audi A8 1994 User manual

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder)
Engine ID AQD APR
Edition 02.1999
Service
Service Department. Technical Information

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
List of Workshop Manual Repair GroupsList of Workshop Manual
Repair GroupsList of Workshop Manual Repair Groups
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder)
Repair Group
01 - Self-diagnosis
24 - Mixture preparation, Injection
28 - Ignition system
Technical information should always be available to the foremen and mechanics, because their careful
and constant adherence to the instructions is essential to ensure vehicle road-worthiness and safety. In
addition, the normal basic safety precautions for working on motor vehicles must, as a matter of course,
be observed.
Service
All rights reserved.
No reproduction without prior agreement from publisher.
Copyright © 2010 Audi AG, Ingolstadt A0050808720

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Contents
01 - Self-diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1 Self-diagnosis of Motronic system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.1 Self-diagnosis of Motronic system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.2 Technical data for self-diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
1.3 Connecting vehicle diagnostic, testing and information system VAS 5051 or fault reader
V.A.G 1551 and selecting functions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2
2 Interrogating and erasing fault memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2.1 Interrogating and erasing fault memory . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
2.2 Fault table . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
3 Final control diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
3.1 Final control diagnosis . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
4 Basic setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
4.1 Basic setting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
5 Coding control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
5.1 Coding control unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
6 Reading measured value block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
6.1 Reading measured value block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .21
24 - Mixture preparation, Injection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
1 Servicing Motronic injection system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
1.1 Servicing Motronic injection system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
1.2 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
1.3 Rules for cleanliness . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .22
1.4 Technical data . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
1.5 Fitting locations overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .23
1.6 Dismantling and assembling fuel rail with injectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .28
1.7 Removing and installing parts of intake manifold change-over . . . . . . . . . . . . . . . . . . . . . .29
1.8 Wiring and component check with test box V.A.G 1598/31 . . . . . . . . . . . . . . . . . . . . . . . . . .30
1.9 Renewing engine control unit -J220 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .31
1.10 Testing idling speed . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .33
1.11 Checking fuel pressure regulator and holding pressure . . . . . . . . . . . . . . . . . . . . . . . . . . . .34
1.12 Checking injectors . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .36
1.13 Testing injection quantity, leak-tightness and spray pattern of injectors . . . . . . . . . . . . . . . .40
1.14 Testing fuel pump relay -J17 and relay activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .42
1.15 Testing air mass meter -G70 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .45
1.16 Checking intake air system for leaks (unmetered air) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .48
1.17 Testing intake air temperature sender -G42 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .49
1.18 Testing coolant temperature sender-G62 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .51
2 Testing lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
2.1 Testing lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
2.2 Operation of lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .52
2.3 Testing lambda probe and lambda control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .53
2.4 Testing lambda probe heating . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .57
2.5 Testing lambda probe signal wiring and activation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .60
2.6 Removing and installing lambda probe . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
3 Testing intake manifold change-over function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
3.1 Testing intake manifold change-over function . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
3.2 Testing operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .63
3.3 Testing intake manifold change-over valve -N156 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .64
3.4 Testing vacuum system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .67
4 Testing secondary air system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
4.1 Testing secondary air system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
4.2 Testing secondary air inlet valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .68
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
Contents i

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
4.3 Testing secondary air pump relay -J299 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .70
5 Testing fuel tank breather system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
5.1 Testing fuel tank breather system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .72
5.2 Testing solenoid valve 1 for activated charcoal filter -N80 . . . . . . . . . . . . . . . . . . . . . . . . . .72
6 Testing electronic engine power control (electronic throttle) . . . . . . . . . . . . . . . . . . . . . . . .76
6.1 Testing electronic engine power control (electronic throttle) . . . . . . . . . . . . . . . . . . . . . . . .76
6.2 Operation of electronic throttle system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
6.3 Testing throttle valve control part -J338 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
6.4 Performing adaption of throttle valve control part . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .76
6.5 Testing angle senders for throttle valve drive . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .79
6.6 Notes on EPC warning lamp (fault warning lamp for electronic throttle) in dash panel insert
. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .80
7 Checking accelerator position senders-G79 and -G185 . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
7.1 Checking accelerator position senders-G79 and -G185 . . . . . . . . . . . . . . . . . . . . . . . . . . . .81
7.2 Checking brake light switch -F and brake pedal switch -F47 . . . . . . . . . . . . . . . . . . . . . . . .83
7.3 Testing clutch pedal switch -F36 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .85
8 Testing auxiliary signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
8.1 Testing auxiliary signals . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
8.2 Checking engine speed signal . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
8.3 Testing air conditioner compressor shut-off . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .88
8.4 Testing data exchange between control units . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .90
28 - Ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1 Testing ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1.1 Testing ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1.2 General notes on ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1.3 Safety precautions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1.4 Technical data for ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .94
1.5 Removing and installing parts of the ignition system . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .95
1.6 Testing ignition coils . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .97
1.7 Testing engine speed sender -G28 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .101
1.8 Checking control unit voltage supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .102
1.9 Testing knock sensor control limit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
1.10 Testing knock sensors-G61and-G66 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .104
1.11 Testing Hall senders-G40and-G163 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .106
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
ii Contents

Protected by copyright. Copying for private or commercial purposes, in part or in whole, is not
permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
01 - Self-diagnosis
1 - Self-diagnosis of Motronic system
1.1 - Self-diagnosis of Motronic system
1.2 - Technical data for self-diagnosis
Equipment
The term "self-diagnosis" relates specifically to the electrical and electronic part of the control system.
The control unit is equipped with a fault memory so that the fault can be traced quickly in the event of an
electronic/electrical component failure or an open circuit.
The advantages of self-diagnosis can only be fully exploited by using the vehicle diagnostic, testing and infor‐
mation system VAS 5051 or the fault reader V.A.G. 1551, in operating mode 1 "Rapid data transfer."
Functions which the vehicle diagnostic, testing and information system VAS 5051 and the fault reader V.A.G
1551 can register => Page 1 , List of selectable functions.
The fault memory is equipped with a non-volatile memory and therefore does not depend on the power supply.
Faults relating to the electronic throttle are also indicated by a warning lamp in the dash panel insert.
Selectable functions when using fault reader V.A.G 1551
The requirements for selecting the desired functions can be taken from the following table.
Address words and functions on
Fault reader V.A.G 1551
Ignition on,
engine not running
Engine idling Vehicle being driven
Address words
00 Automatic test sequence yes yes yes
01 Engine electronics yes yes yes
Functions
01 Interrogate control unit version yes yes yes
02 Interrogate fault memory yes yes yes
03 Final control diagnosis yes no no
04 Basic setting yes yes yes
05 Erase fault memory yes yes yes
06 End output yes yes yes
07 Code control unit yes no no
08 Read measured value block yes yes yes
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
1.1 - Self-diagnosis of Motronic system 1

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
1.3 - Connecting vehicle diagnostic, testing and information system VAS 5051 or fault reader
V.A.G 1551 and selecting functions
Test conditions
• Fuses for engine electronics OK
• Fuel pump relay OK
• Battery voltage at least 11 V
• Earth connections on engine and gearbox OK.
- Switch ignition off.
- -> Connect vehicle diagnostic, testing and information system VAS 5051 with diagnosis cable VAS 5051/1.
As an alternative, connect fault reader V.A.G 1551 with diagnosis cable V.A.G 1551/3.
Warning!
◆ When performing test-drives and checks, the vehicle diagnostic, testing and information system VAS 5051
as well as the fault reader V.A.G. 1551 may be secured only on rear seat, from where it is to be operated.
◆ Please follow safety precautions => Page 22
Note:
The following description only covers the procedure for performing self-diagnosis with fault reader V.A.G 1551.
If using vehicle diagnostic, testing and information system VAS 5051, follow the operating instructions supplied
with the equipment.
-> Indicated on display:
V.A.G - SELF DIAGNOSIS HELP
1 - Rapid data transfer*
2 - Flash code output*
* Appears alternately
- If no display appears, check diagnostic cables:
=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations binder; Fault-finding programme: "Di‐
agnostic wiring"
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
2 01 - Self-diagnosis

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Depending on the function required:
- Switch ignition on.
or
Start the engine
=> Page 1 , table of selectable functions.
- Switch on printer with the Print button
(Warning lamp in button lights up).
- Press key 1 for "Rapid data transfer".
-> Indicated on display:
Rapid data transfer HELP
Enter address word XX
Note:
Address word 00 is used to start the automatic test sequence (i.e. fault memory interrogation for all vehicle
systems with self-diagnosis capability in "Rapid data transfer" mode).
-
Rapid data transfer Q
01 - Engine electronics
-> Press keys 0 and 1 for address word "Engine electronics" and confirm entry by pressing the Q key.
-> If the display shows one of the messages reproduced here, run through the fault-finding procedure as de‐
scribed in the Fault-Finding Programme for diagnosis wiring.
Rapid data transfer HELP
Control unit does not answer
=> Current Flow Diagrams, Electrical Fault-Finding and Fitting Locations
Rapid data transfer HELP
Fault in communication build up
Rapid data transfer HELP
K wire not switching to earth
Rapid data transfer HELP
K wire not switching to positive
-> The display on fault reader V.A.G 1551 will show the control unit identification, as in this example.
3B0907551.. 2.8l V6/5V G
D ..⇒
Coding 05753 WSC 06388
- 3B0907551.. Control unit number
(see Parts List)
- 2.8 ltr. Engine capacity
- V6/5V Engine type
(V engine, 6 cylinders, 5 valves per
cylinder)
- "G"
- or no display
With cruise control (G)
or without cruise control
- D.. Software version in control unit
- Coding 05753 Engine control unit coding; Coding ta‐
ble => Page 19
- WSC 06388 Workshop Code of the V.A.G 1551
with which the last coding was per‐
formed
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
1.3 - Connecting vehicle diagnostic, testing and information system VAS 5051 or fault
reader V.A.G 1551 and selecting functions 3

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
If the coding differs from the vehicle version, then:
- Check control unit coding
=> Coding engine control unit, Page 19
- Press ⇒key.
-> Indicated on display:
Rapid data transfer HELP
Select function XX
Note:
Press the HELP key to obtain a printout of the functions which are available.
2 - Interrogating and erasing fault memory
2.1 - Interrogating and erasing fault memory
- Connect vehicle diagnostic, testing and information system VAS 5051 (or fault reader V.A.G 1551) and
select engine electronics control unit by entering address word "01" ( => Page 2 .)
When doing this the engine must be idling.
Note:
If the engine does not start, turn over the engine with the starter motor for at least 5 seconds, then leave the
ignition switched on.
- Switch on printer with the Print button
(Warning lamp in button lights up).
-> Indicated on display:
Rapid data transfer HELP
Select function XX
- Operate fault reader taking into account the information on the display:
- Press keys 0 and 2 for function "Interrogate fault memory" and confirm entry with Q key.
-> The display will show either the number of faults stored or the message "No fault recognised!".
X Faults recognised!
If no fault is stored:
- Press ⇒key.
If one or more faults are stored:
The faults stored will be displayed and printed out one after the other.
-> Indicated on display:
Rapid data transfer HELP
Select function XX
- Locate and eliminate faults printed out as per fault table
=> Page 5 .
- Press keys 0 and 5 for the function "Erase fault memory" and confirm entry with Q key.
-> Indicated on display:
Rapid data transfer
Fault memory is erased!
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
4 01 - Self-diagnosis

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permitted unless authorised by AUDI AG. AUDI AG does not guarantee or accept any liability
with respect to the correctness of information in this document. Copyright by AUDI AG.
Note:
If the ignition is switched off between interrogating the fault memory and erasing the fault memory, the fault
memory will not be erased. It is therefore important to follow the procedure exactly, i.e. first interrogate the fault
memory and then erase it.
- Press ⇒key.
-> Indicated on display:
Rapid data transfer HELP
Select function XX
- Press keys 0 and 6 for the function "End output" and confirm entry with the Q key.
Automatic test sequence
During test and assembly work faults can be recognised from other control units like e.g. plug disconnected.
Therefore on completion the fault memories of all control units must be interrogated and erased. To do this:
- Press key 0 twice for address word "Automatic test sequence" and confirm entry with Q key. The V.A.G
1551 transmits all known address words one after the other.
When a control unit answers with its identification the number of stored faults appears on the display or "No
fault recognised".
Any system faults that are stored will be displayed one after the other and printed out. The V.A.G 1551 will then
transmit the next address word.
-> The automatic test sequence has ended when the following appears on the display:
V.A.G - SELF-DIAGNOSIS HELP
1 - Rapid data transfer*
2 - Flash code output*
- Erase all fault memories and then carry out a road test.
- Interrogate the fault memories of all control units again using the "automatic test sequence". No faults must
be stored in fault memory.
If no fault is stored:
- Press the ⇒key.
-> Indicated on display:
Rapid data transfer HELP
Select function XX
- Press keys 0 and 6 for the "End data transfer" function and confirm input with the Q key.
2.2 - Fault table
Notes:
◆ If faults occur in the sensors and components being monitored, they will be stored in the fault memory
together with an indication of the type of fault.
◆ Faults relating to the electronic throttle are also indicated by the EPC (Electronic Power Control) warning
lamp in the dash panel insert. Notes on electronic throttle system=>Page 76 .
◆ If the connector for the engine control unit is unplugged or if the battery is disconnected, all the learned
values stored in the control unit will be erased, although the contents of the fault memory will remain intact.
The next time the engine is started the idling may be rough at first.
In addition, the following adaption procedures must be performed => Page 76 .
◆ The fault table is arranged according to the 5-digit fault codes in the left-hand column.
◆ If a fault is stored in the fault memory and then does not occur again during the next 40 engine warm-up
phases, the fault code will be automatically erased.
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
2.1 - Interrogating and erasing fault memory 5

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◆ Sporadically occurring faults (temporary faults) will be indicated on the V.A.G 1551 display as "SP". The
word "sporadic" means "intermittent" or "occurring at irregular intervals".
◆ Components that are indicated as being faulty by the V.A.G 1551/VAS 5051 should not be renewed imme‐
diately. Always start by checking the wiring, connectors and earth connections for the component using the
current flow diagram. This is particularly important in the case of sporadic faults (indicated by the letters
"SP"on the fault reader display).
Fault code Readout on fault reader display Fault rectification
SAE V.A.G
P0102 16486 Air mass meter -G70
Signal too small
Test air mass meter
P0103 16487 Air mass meter -G70
Signal too large
=> Page 45
P0112 16496 Intake air temp. sender -G42
Signal too small
Test intake air temperature sender
P0113 16497 Intake air temp. sender -G42
Signal too large
=> Page 49
P0116 16500 Coolant temp. sender -G62
Implausible signal
Test coolant temperature sender
P0117 16501 Coolant temp. sender -G62
Signal too small
=> Page 51
P0118 16502 Coolant temp. sender -G62
Signal too large
Fault code Readout on fault reader display Fault rectification
SAE V.A.G
P0130 16514 Bank 1, Probe 1
Electrical fault in current circuit
Test lambda control
P0131 16515 Bank 1, Probe 1
Voltage too low
=> Page 52
P0132 16516 Bank 1, Probe 1
Voltage too high
P0134 16518 Bank 1, Probe 1
No activity
Fault code Readout on fault reader display Fault rectification
SAE V.A.G
P0150 16534 Bank 2, Probe 1
Electrical fault in current circuit
Test lambda control
P0151 16535 Bank 2, Probe 1
Voltage too low
=> Page 52
P0152 16536 Bank 2, Probe 1
Voltage too high
P0154 16538 Bank 2, Probe 1
No activity
P0321 16705 Engine speed sender -G28
Implausible signal
Test engine speed sender
=> Page 101
P0322 16706 Engine speed sender -G28
No signal
Fault code Readout on fault reader display Fault rectification
SAE V.A.G
Audi A8 1994 ➤
Motronic injection and ignition system (6-cylinder) - Edition 02.1999
6 01 - Self-diagnosis