Location of Sensor O2 & Running Strange Problem

[ian4455]

Any pics of the location of the O2 sensor on a 3b ?

See comment below added about running problem..

[UrS4boy]

Any pics of the location of the O2 sensor on a 3b ?

Downpipe below wastegate pipe junction.

Here is some G39 O2 sensor info:

http://forums.quattroworld.com/s4s6/msgs/21012.phtml

[ian4455]

Oh... otherwise the Lamda Sensor. Thanks.

Some sensor seems to be upsetting my car as it runs lumpy and black smoke out of exhaust. Switch off the ignition leave for a few minutes, start it back up and its gone !

[UrS4boy]

Oh... otherwise the Lamda Sensor. Thanks. Some sensor seems to be upsetting my car as it runs lumpy and black smoke out of exhaust. Switch off the ignition leave for a few minutes, start it back up and its gone !

Check the O2 ("Lambda" Sensor info link I posted above. It throw a code that you could retrieve to confirm that it is an O2 sensor or not.

It could also be the G62 Coolant Temp Sensor at the back of the head (this is the one that the ECU uses to decide if the engine is cold and needs enriched fuelling or not):

http://forums.quattroworld.com/s4s6/msgs/20985.phtml