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Evaluation display group 032 Display field:
1 / 3 or 2 / 4
Possible cause
Corrective action
Oxygen sensor
adaptation value in
range:
-10.0 to .-25.0 %
Oil thinning- Oil change or perform swift country road
test
High oil consumption
Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking
Page 24
-56
Evaporative Emission (EVAP) canister purge
regulator valve remains stuck in open position - Check Evaporative Emission (EVAP)
Canister Purge Regulator Valve Page 24
-
128
Fuel pressure too high- Check fuel pressure regulator Page 24
-
30
Fuel return line is kinked or clogged.- Check fuel return line.
Fuel injector does not close- Check fuel injectors Page 24
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Evaluation display group 032 Display field:
1 / 3 or 2 / 4
Possible cause
Corrective action
Oxygen sensor
adaptation value in range:
10.0 to 25.0 %
False air in intake area- Check intake system for leaks and repair false
air.
Page 24
-64
.
Fuel pressure too low- Check fuel pressure regulator Page 24
-30
Mass Air Flow (MAF) sensor faulty- Mass Air Flow (MAF) sensor, checking
Page 24
-56
Oxygen sensor heating faulty
Oxygen sensor faulty- Check oxygen sensor heating Page 24
-116
Fuel injector does not open or opens
only partially - Check fuel injectors Page 24
-36
Evaporative Emission (EVAP) Canister
Purge Regulator Valve sticks - Check Evaporative Emission (EVAP) Canister
Purge Regulator Valve Page 24
-128
Ignition coil or spark plug faulty- Check ignition coils Page 28
-7
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Oxygen sensor aging (oxygen sensor
before catalytic converter), checking
Special Tools and Equipment
VAG1788/10 RPM adjuster
Test requirement:
VAS5051 with VAG5051/1
orVAG1551 with VAG1551/3BCoolant temperature at least 80 C Display group 4, display field 3
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24-94
Test sequence
- Connect VAS5051 tester or VAG1551 scan tool
and select the control module for engine
electronics using "address word" 01 Page 01
-
9 .
Engine must run at idle for this.Rapid data transfer
HELP
Select function XX
When indicated on display:
- Press buttons -0- and -4- to select "Initiate basic setting" and press -Q-
button to confirm input.
Basic Settin
g
Q
Input display group number XXX
When indicated on display:
- Press buttons -0-, -3- and -4- to select "display group number 034" and
press -Q- button to confirm input.
System in Basic Setting 34
1
2
3
4
When indicated on display:
Note:
This process can take a few minutes. - Use VAG1788/10 RPM adjuster to adjust engine speed to between
1000 and 2400 RPM.
- Check specified value in display field 4 after indication "Test ON"
appears:
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Display fields
1 2 3 4
Display group 034: Oxygen sensor aging diagnostic, oxygen sensor before catalytic converter (bank 1)
Display xxxx/min
xxx C
x.x s
---
Indicated Engine speed
(RPM) Exhaust
temperature Period duration
Oxygen sensor before
Catalytic converter Diagnostic condition
Functional
range 630 to 6800
70 to 850 C
0 to 3.0 s
Test OFF
Test ON
B1-S2 OK
B1-S2 not OK
Specified
value 1000 to 2400
RPM above 380 C 0.1 to 1.8 s B1-S2 OK
Notes
If the specified value is not reached, replace oxygen sensor 1
before catalytic converter (bank 1)
Note for display field 2:
Calculated value from engine speed and engine load.
Note for display fields 3 and 4:
Period duration is the time between two oxygen sensor voltage jumps (e.g. rich - lean - rich) and is therefore a measurement
of the aging condition of the oxygen sensor. If the specified time is exceeded, display field 4 will indicate = B1-S1 not OK.
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Page 23 of 63
- Press -C- button.Basic Settin
g
Q
Input display group number XXX
When indicated on display:
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- Press buttons -0-, -3- and -5- to select "display
group number 035" and press -Q- button to
confirm input. System in Basic Setting 35
1
2
3
4
When indicated on display:
Note:
The test in display group 035 is activated simultaneously with the test in
display group 034 Therefore the test result is indicated immediately after
display group 035 is selected. - Check specified value in display field 4.
Display fields
1 2 3 4
Display group 035: Oxygen sensor aging diagnostic, oxygen sensor before catalytic converter (bank 2)
Display xxxx/min
xxx C
x.x s
---
Indicated Engine speed
(RPM) Exhaust
temperature Period duration
Oxygen sensor before
Catalytic converter Diagnostic condition
Functional
range 630 to 6800
70 to 850 C
0 to 3.0 s
B1-S2 OK
B1-S2 not OK
Specified
value 1000 to 2400
RPM above 380 C 0.1 to 1.8 s B1-S2 OK
Notes
If the specified value is not reached, replace oxygen sensor 2
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Notes:
The oxygen sensor control behind catalytic
converter overrules the oxygen sensor control
before catalytic converter. It serves as a
corrective control.
Test requirements:
Test sequence
It corrects slight changes in the mixture (i.e. enrichment) via the
oxygen sensor before catalytic converter by holding oxygen sensor
control before catalytic converter at its higher or lower point for a
specific time (dwell time). If this time is in the positive range (i.e. 50
ms), mixture is shifted in the -enrich- direction. If it is in the negative
range (i.e.--50 ms), mixture is shifted in the -lean- direction. Road test performed and DTC memory erased. Coolant temperature at least 80 C Display group 4, display field 3
- Connect VAS5051 tester or VAG1551 scan tool and select the control
module for engine electronics using "address word" 01 Page 01
-9 .
Engine must run at idle for this.
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