S3 8L Lambda problem

[shineydave]

just done a scan and a bit of logging for an S3 owner. Vag-Com reported no faults but the Maf is showing a peak flow of 190g/s. it's had a custom code map on it so i think it should be higher than that possibly nearer to 220g/s to equate to the 260bhp, he's been told he has.

the Lambda is constant at -3.1, i'm fairly certain that mine on the S4 fluctuates as it measures the fluctuations in AFR, does it sound like the Lambda is Donald?

it seems like the Lambda is constantly reporting a rich mixture and the ECU is backing off the injector timing to compensate causing the missing 20bhp