Couple of fault codes on my mates 3.2?

[-Ju-]

A mate has an 04 plate 3.2 dsg and recently has had the engine light pop on a couple of times, the first time I deleted the code and left it at that but today it reappeared with another code as well.


Address 01: Engine Labels: 022-906-032-BDB.lbl
Control Module Part Number: 022 906 032 CB HW: Bas isX 3
Component and/or Version: MOTRONIC ME7.1.1 5604
Software Coding: 0000178
Work Shop Code: WSC 06435 000 00000
VCID: 4D9A6966AD57
2 Faults Found:

19598 - Oxygen (Lambda) Sensor B2 S1: Signal Implausibly Lean
P3142 - 008 - Implausible Signal - Intermittent
17599 - Linear O2 Sensors: Before CAT: Reversed
P1191 - 008 - Implausible Signal - Intermittent

Readiness: 0000 0100

The first code is the one that appeared last time, as regards the second one, the sensors and wiring etc. have never been touched so that is a strange one.
Apart from the codes, the car runs fine and has only done 29k miles

Any ideas anyone?

 

[IN-A3]

Hi had a lambda go down last year. These sensors dont fail completely but dropout at odd points in there temperture range.

also check for a broken earth strap ( its the metal rod from the gearbox to the mainifold) Cost less then 10 quid with new bolts. Mine was broken under the head of the bolt.

B2 S1 is the nearside sensor.

Remove the air filter and air box to make access eaiser.

 

[-Ju-]

Cheers for the reply. I remember the earth strap as that was missing on mine when I bought it.
As for the Lambda, I take it that's the one pre cat i.e. in the actual downpipe?
Don't know why it's saying the lambda's are reversed though, maybe it's just getting confused with the other fault being present.