# Faulty O2/Lamdba Sensor?



## bartus (Jan 10, 2013)

Hi guys, after changing the EGR valve the other month the engine management light has come back on, the cur runs ok, seems sluggish when accelerating. I have invested in the VCDS kit and the error codes are as follows: 

Address 01: Engine Labels: 036-906-034-APE.lbl
Part No: 036 906 034 D
Component: MARELLI 4LV 3979 
Coding: 00031
Shop #: WSC 00000 
VCID: 132575C061627D808CE

4 Faults Found:
17582 - Fuel Trim; Bank 1 
P1174 - 35-00 - Injection Timing Deviation (Balance Fault)
16710 - Knock Sensor 1 (G61) 
P0326 - 35-00 - Implausible Signal
17598 - Linear O2 Sensor; Reference Voltage 
P1190 - 35-10 - Implausible - Intermittent
17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1 
P1196 - 35-10 - Electrical Malfunction - Intermittent
Readiness: 1010 0001

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Address 03: ABS Brakes Labels: 6X0-907-379.lbl
Part No: 6X0 907 379 B
Component: ABS 30 IE CAN V004 
Coding: 05603
Shop #: WSC 00788 
VCID: 4385858051822D007CE

2 Faults Found:
01276 - ABS Hydraulic Pump (V64) 
16-10 - Signal Outside Specifications - Intermittent
00290 - ABS Wheel Speed Sensor; Rear Left (G46) 
35-10 - - - Intermittent


To me it looks like an o2 sensor fault (and an ABS fault), the car (vw polo 6n2 2001 1.4 16v) has two o2 sensors, i believe it to be the first (pre cat) lambda sensor, can anyone confirm it needs replacing before i fork out for a new one.

Thanks.


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## ghostridersa (Jan 5, 2013)

You need to post a complete auto scan, (in other words an auto scan including the part where your genuine vcds version details will be), in your posted scan it does not show up.


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## bartus (Jan 10, 2013)

Auto scan!

Thursday,03,January,2013,18:32:02:06133
VCDS Version: Release 11.11.5
Data version: 20121222
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Chassis Type: 6N - VW Polo
Scan: 01 02 03 08 15 17 19 25 41 45 46 55 56

VIN: WVWZZZ6NZ1Y322383 Mileage: 111830km/69487miles
-------------------------------------------------------------------------------
Address 01: Engine Labels: 036-906-034-APE.lbl
Part No: 036 906 034 D
Component: MARELLI 4LV 3979 
Coding: 00031
Shop #: WSC 00000 
VCID: 132575C061627D808CE

4 Faults Found:
17582 - Fuel Trim; Bank 1 
P1174 - 35-00 - Injection Timing Deviation (Balance Fault)
16710 - Knock Sensor 1 (G61) 
P0326 - 35-00 - Implausible Signal
17598 - Linear O2 Sensor; Reference Voltage 
P1190 - 35-10 - Implausible - Intermittent
17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1 
P1196 - 35-10 - Electrical Malfunction - Intermittent
Readiness: 1010 0001

-------------------------------------------------------------------------------
Address 03: ABS Brakes Labels: 6X0-907-379.lbl
Part No: 6X0 907 379 B
Component: ABS 30 IE CAN V004 
Coding: 05603
Shop #: WSC 00788 
VCID: 4385858051822D007CE

2 Faults Found:
01276 - ABS Hydraulic Pump (V64) 
16-10 - Signal Outside Specifications - Intermittent
00290 - ABS Wheel Speed Sensor; Rear Left (G46) 
35-10 - - - Intermittent

-------------------------------------------------------------------------------
Address 15: Airbags Labels: 6Q0-909-605-VW5.lbl
Part No: 6Q0 909 601 
Component: 2A AIRBAG VW5 0006 
Coding: 12865
Shop #: WSC 00788 
VCID: F0EF9A4CB0B4669851C

No fault code found.

-------------------------------------------------------------------------------
Address 17: Instruments Labels: 6N0-920-xxx-17.lbl
Part No: 6N0 920 904 D
Component: KOMBIINSTRUMENT BOO V12 
Coding: 00441
Shop #: WSC 00655 
VCID: 306FDA4CF034A69891C

No fault code found.

-------------------------------------------------------------------------------
Address 19: CAN Gateway Labels: 6N0-909-901-19.lbl
Part No: 6N0 909 901 
Component: Gateway KCAN 
Coding: 00022
Shop #: WSC 00000 
VCID: F0EF9A4CB0B4669851C

No fault code found.

-------------------------------------------------------------------------------
Address 25: Immobilizer Labels: 6X0-953-257.lbl
Part No: 6X0 953 257 
Component: IMMO 0008 
Coding: 00001
Shop #: WSC 00000 
VCID: FDF1B378F7E61BF0CAA
WVWZZZ6NZ1Y322383 VWZ1Z0A1495538

No fault code found.

End ---------------------------------------------------------------------


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## ghostridersa (Jan 5, 2013)

Thanks for your autoscan. Ok lets deal with your fault codes, Firstly I need you to clear the codes and take it for a drive and then scan engine again and let me know if the exact same codes are coming back. (You might have old codes stored so its best to clear, drive and re-scan then deal with the codes which come back.

If you have a multimeter I need you to start checking the O2 sensor readings at the ecu multi plug. Do you have autodata by any chance. Reading should be as follows at ecu if you pin it out:

Terminal 51 & earth , engine warm and at idle 3.8v
Terminal 70 & earth, engine warm and at idle 4.25v
Terminals 51 & 70, engine warm and at idle 0.46v

The ecu's on these vehicle tend to at times become faulty and thrown O2 sensor codes. However at the same time this having been said it could very well be you O2 sensor which is faulty. Lets see what readings you come back with and take it from there.


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## bartus (Jan 10, 2013)

Hi i have cleared the codes and driven about 50 miles, the only code i am now seeing is the knock sensor one (and the ABS but will worry about that another day): 

Am going to get a multimeter on the sensor tomorrow.

Friday,11,January,2013,19:47:11:06133
VCDS Version: Release 11.11.5
Data version: 20121222
--------------------------------------------------------------------------------
--------------------------------------------------------------------------------
Address 01: Engine Labels: 036-906-034-APE.lbl
Control Module Part Number: 036 906 034 D
Component and/or Version: MARELLI 4LV 3979
Software Coding: 00031
Work Shop Code: WSC 00000 
VCID: 132575C061627D808CE
1 Fault Found:

16710 - Knock Sensor 1 (G61) 
P0326 - 35-00 - Implausible Signal

Readiness: 1010 0001


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## bartus (Jan 10, 2013)

Have tried to read the pin data but have not had much luck, finally got to the ECU, what is the best way to physically get to the pins with the connector still connected?


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## ghostridersa (Jan 5, 2013)

You can learn how to back probe at the attached link. Shout if you need help. http://jaywilliamsfuels.blogspot.com/2011/07/back-probing.html


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## bartus (Jan 10, 2013)

Now the snow has finally gone, i have had a try at this, attempted at the ECU but its just too fiddley with the small size of the connectors etc.

What probe tests can i do a the the o2 sensor connector? will this be as accurate results? 

The MIL light has come back on after nearly 300 miles since i last cleared the codes. These were the codes this time around.... (can post the whole auto scan if needed)

3 Faults Found:
16710 - Knock Sensor 1 (G61) 
P0326 - 35-00 - Implausible Signal
17978 - Engine Start Blocked by Immobilizer 
P1570 - 35-10 - - Intermittent
17604 - Oxygen (Lambda) Sensor Heater Circuit: B1 S1 
P1196 - 35-10 - Electrical Malfunction - Intermittent

Thanks


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## [email protected] Parts (Nov 27, 2006)

Content was vacated by JACK :heart:


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## bartus (Jan 10, 2013)

Changed the O2 sensor a few weeks ago, car seems a little more efficient but still a lack off power.

Knock sensor fault has triggered again within a few miles of driving.

Have done a compression test, all cylinders seems fine 240 | 200 | 240 | 240 (psi) 

Have done some reading about a broken/clogged Catalytic Converter can cause a massive loss in power... 

Have done some data logging from what i think are the correct measuring blocks:
Group 34 - Field 1 - Exhaust Gas Temp - (before CAT)
Group 46 - Field 1 - Catalytic Converter - Temperature

Both temperatures are coming out exactly the same, were as the cat should be hotter than the pre-cat, so is my assumption that the cat is broken correct, or are the measuring blocks incorrect?

Thanks.


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