Lambda Sensor

[GTG40]

Have a look at the graph the lambda is in yellow (revs: Blue)
Dosen't seem very consistant.
do you rekon its broke?

 [attachment=111]

cheers

[hayesey]

the lambda will cycle inbetween 0-1 volt at idle that's normal.  Also you need to ignore any values it gives till it up to temp which takes a few minutes, lambda probes dont work when cold so will give off daft readings.

Are all the graphs inverted?  Quite confusing!  I would say it appears to be ok though but your idle looks pretty rough esp since it seems to dip down to 500rpm at one point.  The lambda is used on part throttle so try to get some logging done while driving the car using a range of RPM and engine loads.  Obviously you need a laptop to do that!

[GTG40]

[quote pid=3487 author=hayesey date=1219354539]the lambda will cycle inbetween 0-1 volt at idle that's normal.  Also you need to ignore any values it gives till it up to temp which takes a few minutes, lambda probes dont work when cold so will give off daft readings.

Are all the graphs inverted?  Quite confusing!  I would say it appears to be ok though but your idle looks pretty rough esp since it seems to dip down to 500rpm at one point.  The lambda is used on part throttle so try to get some logging done while driving the car using a range of RPM and engine loads.  Obviously you need a laptop to do that![/quote]

Thanks for the advise i'll record some values while driving.

It runs at low rpm when cold, when i'm driving its fine, its when its ticking over. then when its warm then it ticks over alot better. i've changed the blue temp sensor (VW) but that didn't make much difference.

[hayesey]

I doubt that's the lambda as it's not used by the ecu when the car is cold, it only comes into effect when it is warm.

But the best thing to do is to do some logging like you have been doing but all as many sensors as you can!  Also check out the engine diagnosis guide in the FAQ section.