1999 AUDI A4 engine

01-52

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0170 / 16554
Fuel Trim Malfunction (Bank 1) Air leak in the area of the intake
manifold

- Find and repair leak

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
check DTC memory again

Oil dilution (fuel in the oil) because
of frequent cold starts or driving short
distances

- Check, if necessary do oil change
MIL Status:
MIL lights up after 2 Trips Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
check DTC memory again

Mass Air Flow (MAF) sensor -G70-
supplies false signal

- Check Mass Air Flow (MAF) sensor -
G70- page 24
-81

For troubleshooting Display
groups 005, 007, 009 and 010
Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
check DTC memory again

Oil burning with faulty piston

Repair Manual, 2.8 Liter V6 2V Engine
Mechanical, Engine Code(s): AFC, Repair Group 15
- Check compression pressure

Malfunction cause found: Yes

Pa
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) - Multi
port Fuel In
jection
(MFI
)
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p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-56

Output on GST and/or on
VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0173 / 16557
Fuel Trim Malfunction (Bank 2) Air leak in the area of the manifold

- Find and repair leak

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
check DTC memory again

Oil diluted (fuel in the oil) because
of frequent cold starts for driving short
distances

- Check and change oil if necessary
MIL Status:
MIL lights up after 2 Trips Malfunction cause found: Yes
No

- Erase DTC memory, test drive and
check DTC memory again

Mass Air Flow (MAF) sensor -G70-
supplies false signal

- Check Mass Air Flow (MAF) sensor -
G70- page 24
-81

For troubleshooting Display
groups 006, 008, 009 and 010
Malfunction cause found: Yes
No
Continued next page

- Erase DTC memory, test drive and
check DTC memory again

Oil burning with faulty piston

Repair Manual, 2.8 Liter V6 2V Engine
Mechanical, Engine Code(s): AFC, Repair - Check compression pressure
Pa
ge 77 of 366 On Board Dia
gnostic
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) - Multi
port Fuel In
jection
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)
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yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-68

Output on GST and/or
on VAG 1551 scan tool Possible malfunction cause

Malfunction repair
P0322 / 16706
Ignition/Distributor Engine
Speed Input Circuit No
Signal Malfunction P1339 / 17747
"Crankshaft Pos./Engine Speed
Sensors Cross connected" also in
DTC memory
No
Yes

- 3-pin harness connector on Crankshaft Position
(CKP) sensor -G4- and engine speed (RPM) sensor
-G28- transposed disconnect both connectors and
connect correctly; installation location page 28
-7

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again
MIL Status:
MIL lights up
immediately
Harness connector for engine
speed (RPM) sensor -G28- loose
or corroded due to moisture in the
harness connector

- Check harness connector for tight fit and contact
corrosion, if necessary reconnect and/or clean,
installation page 28
-7

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again

Holding socket for engine
speed (RPM) sensor -G28- loose
or -G28- incorrectly adjusted

- Check mounting
- Adjust engine speed bracket page 28
-23

Malfunction cause found: Yes
No
Continued next page

- Erase DTC memory, test drive and check DTC
memory again
Pa
ge 92 of 366 On Board Dia
gnostic
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) - Multi
port Fuel In
jection
(MFI
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-69


Metal chips on engine speed (RPM) sensor -G28- or
distance from the engine speed (RPM) sensor -G28- to the
flywheel ring greater than 1.2 mm (0.049 in.)

- Remove engine speed (RPM) sensor -G28-,
check for contamination, clean if necessary

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again

Wiring connection to engine speed (RPM) sensor -G28-
faulty or sensor -G28- faulty

- Check and adjust engine speed (RPM) sensor -
G28- page 28
-21


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC
memory again

Engine Control Module (ECM) -J192- faulty

- Replace and code engine control module
page 01
-265
erase DTC memory and test drive
check DTC memory
Note:
If the malfunction "P0322 / 16706" is recognized during engine start, no ignition or fuel injection occurs.
Pa
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) - Multi
port Fuel In
jection
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)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-71


Wiring connection to Knock Sensor (KS) 1 -
G61- faulty, or sensor -G61- faulty

- Check knock sensor 1 -G61- page 28
-29

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and check DTC memory again

Engine Control Module (ECM) -J192- faulty

- Replace and code engine control module page 01
-265

erase DTC memory and test drive check DTC memory
Note:
The malfunction "P0327 / 16711" is set if the output voltage of the knock sensor is too low (below 0.2 V) (coolant temperature
over 20 C (68 F)/ engine speed greater than 3500 RPM and engine load greater than 16%). The ignition angle is then
retarded by 12 crankshaft in the knocking areas of the map (engine load greater than 40%).
Pa
ge 96 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-73


Wiring connection to Knock Sensor (KS) 2 -
G66- faulty or sensor -G66- faulty

- Check knock sensor 2 -G66- page 28
-29

Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test drive, check DTC
memory again

Engine Control Module (ECM) -J192- faulty

- Replace and code engine control module page 01
-265

erase DTC memory and test drive check DTC memory
Note:
The malfunction "P0332 / 16716" is set when the knock sensor output voltage is too low (under 0.2 V) (coolant temperature
over 20 C (68 F) / engine speed greater than 3500 RPM and engine load greater than 16%). The ignition angle is then
retarded by 12 crankshaft in the knocking ranges of the map (engine load greater than 40%).
Pa
ge 99 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-75


Engine Control Module
(ECM) -J192- faulty

- Replace and code engine control module page 01
-265
erase DTC
memory and test drive check DTC memory
Note:
The malfunction "P0337 / 16721" is set at an engine speed between 25 RPM and 400 RPM as soon as no crankshaft sensor
signal is recognized for longer than 3 sec.
Pa
ge 102 of 366 On Board Dia
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) - Multi
port Fuel In
jection
(MFI
)
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play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1

01-77


EGR vacuum regulator solenoid valve -N18- sticks
in closed position

- Check EGR vacuum regulator solenoid valve -N18-
page 24
-67


Malfunction cause found: Yes
No

- Erase DTC memory, test drive and after test drive, check
DTC memory again

EGR valve sticks in closed position

- Check mechanical EGR valve page 24
-70

Malfunction cause found: Yes


- Erase DTC memory, test drive and after test drive, check
DTC memory again
Notes:

Recognition condition for the malfunction "P0401 / 16785" (mech. valve continuously closed) is a coolant temperature over
72 C (162 F), an open idle switch, a throttle angle less than 42.5 , a vehicle speed between 70 km/h and 105 km/h (44
and 66 mph), an EGR duty cycle greater than 50%, an engine speed between 1500 RPM and 3300 RPM and an engine
load between 23% and 60%. If all these conditions are fulfilled and the EGR temperature signal is less than 50 C (122
F) for longer than 34 sec, the malfunction "P0401 / 16785" is set.
Pa
ge 104 of 366 On Board Dia
gnostic
(OBD
) - Multi
port Fuel In
jection
(MFI
)
11/22/2002 htt
p://127.0.0.1:8080/audi/servlet/Dis
play?action=Goto&t
yp
e=re
pair&id=AUDI.B5.FU01.01.1