Lambda Fault?

flooky

Guest
Is there a way of finding out im my lambda sensor is gone using VAG-COM?

The car has just passed the MOT without any problem and when I checked for any faults and there was 1 leak in the system. Rendiness (how ever it spelt) came up with all ok and no faults but now tonight I checked it again and the lambda, cat and summit else is not responding?

Would there be anywhere on VAG-COM to show what it's reading and what it's ment to be?
 

flooky

Guest
Here are my readings for my MAF tho im not sure what it should be reading?

Wednesday,17,January,2007,12:47:35
6K0 906 032 ,,1.8L R4/20VT SEA 0002,

,Group A:,'002,,,,Group B:, Not Running,,,,Group C:, Not Running,,RPM,Load,Inj. On Time,Mass Flow,,,,,,,,,,
,TIME,,,,,TIME,,,,,TIME,,,,
MARKER,STAMP, /min,%, ms, g/s,STAMP,,,,,STAMP,,,,
Code:
,0.01,840,18.0,2.46,3.03,,,,,,,,,,
,0.59,840,18.0,2.46,2.94,,,,,,,,,,
,1.21,1040,45.9,7.38,11.33,,,,,,,,,,
,1.83,1760,51.9,7.38,18.22,,,,,,,,,,
,2.47,1920,54.9,8.20,21.75,,,,,,,,,,
,3.14,2240,59.4,9.43,27.33,,,,,,,,,,
,3.73,3080,61.7,9.43,37.89,,,,,,,,,,
,4.31,3880,65.4,9.84,49.11,,,,,,,,,,
,4.90,4760,71.4,11.07,66.06,,,,,,,,,,
,5.54,5360,71.4,11.07,73.50,,,,,,,,,,
,6.14,5840,68.4,10.66,77.19,,,,,,,,,,
,6.72,6200,67.7,11.07,80.53,,,,,,,,,,
,7.34,6560,60.2,8.20,66.64,,,,,,,,,,
,8.01,5360,8.3,1.23,6.92,,,,,,,,,,
,8.73,4120,62.4,9.43,53.06,,,,,,,,,,
,9.31,4480,72.9,11.07,64.47,,,,,,,,,,
,9.92,4800,73.7,11.07,67.39,,,,,,,,,,
,10.50,5080,72.2,11.07,69.83,,,,,,,,,,
,11.15,5360,69.9,10.66,71.89,,,,,,,,,,
,11.74,5600,69.2,10.66,73.86,,,,,,,,,,
,12.31,5760,68.4,10.66,75.50,,,,,,,,,,
,12.98,5960,67.7,10.66,76.47,,,,,,,,,,
,13.61,6160,66.2,10.66,77.61,,,,,,,,,,
,14.29,6360,64.7,10.66,79.50,,,,,,,,,,
 
Last edited by a moderator:

bigjode

Full Member
Feb 25, 2006
504
0
The Maf can read low and yet the car won't know its a fault unless its reading zero - as far as the car is concerned a low reading just means less air, not a faulty MAF.

But by doing logs like you have done, you have found the fault.

And that MAF is DEFINATELY shagged m8!
 

bigjode

Full Member
Feb 25, 2006
504
0
oh, for Lambda- log block 031- if it has two lambda readings then it can read it (some cars have a wide band sensor that reads lambda, some don't).

You want Lambda to be around 1 - it will fluctuate though like 0.8 to 1.2
 

flooky

Guest
ok thanks, i been looking at other posts and realise mine is well low... would a temp sender fault cause this problem also? thought I read it would?

so guess i'll have to get another MAF then! bugger. Long as nothing else can be causing my problem also.
 

flooky

Guest
oh, should i do any other logs on things that i should be aware of if the car is hesiting when on boost from 4k +?
 

bigjode

Full Member
Feb 25, 2006
504
0
log block 118 - that shows what the N75 is doing to the wastegate to control boost, log 115 - that shows how much boost the ECU wants vs how much the car actually produces - helps diagnose leaks etc,

020 is good one to know, it shows timing pull - doesn't sound like thats your probmlem at the moment, but for future notice ;)
 

flooky

Guest
oh what would happen if i was to unplug or clean my maf? i know where i can get a new maf from a independent vag dealer.
 

flooky

Guest
SORRY IVE NO IDEA HOW TO MAKE THIS LOG CLEAN!





****This was a lambda test sat on idle****

Thursday,18,January,2007,11:22:46
6K0 906 032 ,,1.8L R4/20VT SEA 0002,

,Group A:,'031,,,,Group B:, Not Running,,,,Group C:, Not Running
,,Voltage,Voltage,Bin. Bits,Bin. Bits,,,,,,,,,,
,TIME,,,,,TIME,,,,,TIME,,,,
MARKER,STAMP, V, V,,,STAMP,,,,,STAMP,,,,
,0.01,0.595,0.460, , ,,,,,,,,,,
,0.60,0.090,0.480, , ,,,,,,,,,,
,1.11,0.660,0.445, , ,,,,,,,,,,
,1.71,0.095,0.420, , ,,,,,,,,,,
,2.32,0.180,0.430, , ,,,,,,,,,,
,2.92,0.675,0.420, , ,,,,,,,,,,
,3.60,0.085,0.435, , ,,,,,,,,,,
,4.29,0.705,0.430, , ,,,,,,,,,,
,4.81,0.105,0.440, , ,,,,,,,,,,
,5.42,0.130,0.450, , ,,,,,,,,,,
,6.01,0.710,0.430, , ,,,,,,,,,,
,6.62,0.650,0.455, , ,,,,,,,,,,
,7.24,0.080,0.475, , ,,,,,,,,,,
,7.86,0.160,0.440, , ,,,,,,,,,,
,8.48,0.690,0.420, , ,,,,,,,,,,
,9.12,0.100,0.435, , ,,,,,,,,,,
,9.73,0.695,0.430, , ,,,,,,,,,,
,10.32,0.110,0.455, , ,,,,,,,,,,
,10.89,0.120,0.470, , ,,,,,,,,,,
,11.40,0.695,0.440, , ,,,,,,,,,,
,12.00,0.085,0.445, , ,,,,,,,,,,
,12.60,0.685,0.450, , ,,,,,,,,,,
,13.20,0.105,0.445, , ,,,,,,,,,,
,13.90,0.690,0.455, , ,,,,,,,,,,
,14.61,0.795,0.445, , ,,,,,,,,,,
,15.20,0.055,0.520, , ,,,,,,,,,,
,15.80,0.065,0.505, , ,,,,,,,,,,
,16.40,0.105,0.425, , ,,,,,,,,,,
,17.01,0.635,0.380, , ,,,,,,,,,,
,17.62,0.070,0.375, , ,,,,,,,,,,
,18.21,0.090,0.355, , ,,,,,,,,,,
,18.81,0.750,0.350, , ,,,,,,,,,,
,19.51,0.065,0.395, , ,,,,,,,,,,
,20.20,0.075,0.380, , ,,,,,,,,,,
,20.81,0.685,0.335, , ,,,,,,,,,,
,21.40,0.660,0.375, , ,,,,,,,,,,
,22.00,0.065,0.435, , ,,,,,,,,,,
,22.60,0.100,0.345, , ,,,,,,,,,,
,23.21,0.710,0.340, , ,,,,,,,,,,
,23.85,0.075,0.460, , ,,,,,,,,,,
,24.48,0.725,0.380, , ,,,,,,,,,,
,25.10,0.335,0.505, , ,,,,,,,,,,
,25.71,0.070,0.540, , ,,,,,,,,,,
,26.31,0.675,0.390, , ,,,,,,,,,,
,26.90,0.575,0.390, , ,,,,,,,,,,
,27.51,0.110,0.485, , ,,,,,,,,,,
,28.11,0.560,0.390, , ,,,,,,,,,,
,28.71,0.080,0.505, , ,,,,,,,,,,
,29.36,0.725,0.435, , ,,,,,,,,,,
,29.98,0.110,0.490, , ,,,,,,,,,,
,30.60,0.095,0.490, , ,,,,,,,,,,
,31.19,0.805,0.435, , ,,,,,,,,,,
,31.79,0.760,0.540, , ,,,,,,,,,,
,32.39,0.085,0.535, , ,,,,,,,,,,
,32.98,0.110,0.500, , ,,,,,,,,,,
,33.60,0.735,0.465, , ,,,,,,,,,,
,34.21,0.785,0.475, , ,,,,,,,,,,
,34.83,0.785,0.520, , ,,,,,,,,,,
,35.49,0.760,0.530, , ,,,,,,,,,,
,36.20,0.715,0.525, , ,,,,,,,,,,
,36.82,0.710,0.520, , ,,,,,,,,,,
,37.40,0.630,0.510, , ,,,,,,,,,,
,37.99,0.080,0.495, , ,,,,,,,,,,
,38.59,0.215,0.470, , ,,,,,,,,,,
,39.19,0.550,0.440, , ,,,,,,,,,,
,39.81,0.645,0.430, , ,,,,,,,,,,
,40.47,0.080,0.430, , ,,,,,,,,,,
,41.19,0.680,0.415, , ,,,,,,,,,,
,41.78,0.095,0.415, , ,,,,,,,,,,
,42.30,0.110,0.420, , ,,,,,,,,,,
,42.88,0.700,0.410, , ,,,,,,,,,,
,43.51,0.090,0.425, , ,,,,,,,,,,
,44.07,0.110,0.440, , ,,,,,,,,,,
,44.68,0.305,0.425, , ,,,,,,,,,,
,45.31,0.080,0.430, , ,,,,,,,,,,
,45.98,0.100,0.415, , ,,,,,,,,,,
,46.68,0.690,0.410, , ,,,,,,,,,,
,47.28,0.660,0.430,


---------------------------------------------------------------------------------------------------


THIS IS WHEN THE CAR WAS JERKEY ON BOOST


Thursday,18,January,2007,11:29:54
6K0 906 032 ,,1.8L R4/20VT SEA 0002,

,Group A:,'002,,,,Group B:,'001,,,,Group C:,'115
,,RPM,Load,Inj. On Time,Mass Flow,,RPM,Temperature,Lambda,Bin. Bits,,RPM,Load,Absolute Pres.,Absolute Pres.
,TIME,,,,,TIME,,,,,TIME,,,,
MARKER,STAMP, /min,%, ms, g/s,STAMP, /min,°C,%,,STAMP, /min,%, mbar, mbar
,0.65,2120,75.2,11.07,31.25,1.32,2240,79.0,25.0,01101000,1.93,2360,77.4,1500.0,1520.0
,2.52,2440,77.4,11.48,36.33,3.13,2560,79.0,25.0,01101000,3.72,2680,75.9,1510.0,1520.0
,4.31,2760,75.9,11.07,39.67,4.95,2840,79.0,25.0,01101000,5.63,2960,75.9,1490.0,1510.0
,6.34,3040,75.9,11.48,44.11,6.94,3160,80.0,25.0,01101000,7.52,3240,75.2,1460.0,1500.0
,8.11,3320,75.2,11.07,48.22,8.72,3400,79.0,25.0,01101000,9.33,3480,74.4,1450.0,1480.0
,9.96,3560,73.7,11.07,50.47,10.56,3640,80.0,25.0,01101000,11.24,3720,72.9,1440.0,1460.0
,11.91,3800,72.2,10.66,53.19,12.46,3880,79.0,25.0,01101000,13.01,3960,72.2,1450.0,1450.0
,13.63,4040,71.4,10.66,55.31,14.23,4080,79.0,25.0,01101000,14.84,4160,72.2,1450.0,1450.0
,15.49,4240,72.2,10.66,57.69,16.08,4320,79.0,25.0,01101000,16.74,4320,72.9,1440.0,1470.0


-----------------------------------------------------------------------------------------------


BELIEVE IT OR NOT BUT WHEN THIS LOG WAS DONE THE CAR RAN FINE WITHOUT ANY PROBLEMS!


Thursday,18,January,2007,11:34:30
6K0 906 032 ,,1.8L R4/20VT SEA 0002,

,Group A:,'002,,,,Group B:,'118,,,,Group C:,'115
,,RPM,Load,Inj. On Time,Mass Flow,,RPM,Temperature,Load,Absolute Pres.,,RPM,Load,Absolute Pres.,Absolute Pres.
,TIME,,,,,TIME,,,,,TIME,,,,
MARKER,STAMP, /min,%, ms, g/s,STAMP, /min,°C,%, mbar,STAMP, /min,%, mbar, mbar
,0.59,2040,21.8,3.69,8.56,1.17,2080,26.0,0.0,1000.0,0.01,2040,19.5,990.0,1000.0
,2.38,2160,20.3,3.28,8.58,2.99,2200,26.0,0.0,1000.0,1.77,2120,21.1,990.0,1010.0
,4.24,2720,64.7,10.66,37.00,4.89,3160,24.0,49.0,1490.0,3.57,2440,54.1,1520.0,1060.0
,6.19,4120,72.9,11.89,57.78,6.77,4520,24.0,55.3,1500.0,5.57,3680,72.9,1480.0,1500.0
,7.98,5200,70.7,11.48,70.47,8.58,5560,27.0,59.2,1470.0,7.39,4920,73.7,1470.0,1480.0
,10.01,6080,66.9,11.48,78.39,10.70,5480,30.0,0.0,1250.0,9.26,5800,68.4,1480.0,1470.0
,11.88,4400,72.2,11.89,62.39,12.47,4560,31.0,54.9,1500.0,11.28,4240,62.4,1430.0,1330.0
,13.69,4840,71.4,11.89,67.25,14.32,5000,33.0,54.9,1480.0,13.10,4720,72.9,1450.0,1470.0
,15.71,5320,68.4,11.48,69.92,16.38,5440,35.0,56.9,1470.0,14.96,5160,70.7,1470.0,1460.0
,17.58,5680,67.7,11.48,73.72,18.19,5760,37.0,61.6,1480.0,16.98,5560,67.7,1490.0,1470.0
,19.38,5960,66.2,11.48,75.08,20.03,5120,36.0,0.0,1180.0,18.78,5880,66.9,1430.0,1470.0
 

bigjode

Full Member
Feb 25, 2006
504
0
Maf readings are definately low, doesn't look like you have a boost leak though.

You havn't the wide band sensor on your car from the looks of block 031 - so I can't comment on the lambda. Other way to see A/F ratio is to download this:
http://www.ross-tech.net/vag-com/examples/air_fuel_EXAMPLE.xls

its an excel spreadsheet and if you copy and paste your block 002 results, it will show you your A/F ratio.

BUT remember, problems with A/F ratio can be down to lots of things, not just a faulty Lambda sensor.

PS to make a log look clean in a post, put ["code"] at the beginning and ["/code"] at the end, just like that with the square brackets etc. (not including " " )
 

bigjode

Full Member
Feb 25, 2006
504
0
oh what would happen if i was to unplug or clean my maf? i know where i can get a new maf from a independent vag dealer.

your MAF is 100% Faulty. I think you'll be surprised how much difference a new one will make ;)

Dealers sell them and GSF parts sell them - if you give em your fauty one its about £75 at GSF.

I don't think cleaning it will help yours, its too far gone! unplugging it may make it drive smoother, but its bad for the car as it can't control fueling properly.
 

flooky

Guest
na i think ive sorted the boost leak when i replaced my vac hoses with some nice samco stuff :D

yeah i can see the maf readings are low :( it's just so weird how when i can take it down the bypass and have this fault and turn around and do the same but yet the car is fine?

so from what i got u think my lambda readings are low? and if so would the maf be the main reason behind this? im just not sure now what to do.

Ive also got a low signal from the temp sender so i'll get one of these tomz.. someone did say this mite have an effect on things?

what do you think i should do now?
 

bigjode

Full Member
Feb 25, 2006
504
0
No, your Lambda readings aren't how i'm used to seeing them, because my sensor is different to yours - I don't know what yours mean.

Temp sensor can cause problems too, but usually brings up a fault straight away.

MAF! MAF! MAF! MAF! :clap:
 

flooky

Guest
ok fair enough! see your point!

it's always read as a fault since i got vag-com..

i'll see what i can do for a new temp & man sensor tomorrow then.. see if i can get some trade!

will let ya know how it goes!

cheers! i think? god dam maf!!!
 
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