New S3 owner, running lean on dyno?

[Machine212]

Hey i recently got my self an s3, love it! Thought id take it up to the RR and get the power checked. The dyno said i had 214bhp which i thought was ok for a 12 year old motor. But the strange thing was that the lambda sensor (on the dyno, not the car) read the same all the way along the run until the very end where it ups the fueling. The guy showed me a few graphs from other S3 runs and they all gradually up fueling along the chart. Its also not like it goes lean as the RPM goes up, It just sit steady then ups the fuel at the end.
Any idea what could cause this? Also the car already has a brand new bosch maf, first thing i fitted.

 

[<tuffty/>]

What year/engine code? AMK/BAM S3's run lambda 1 pretty much all day long unless protection maps kick in to enrichen it a bit...

This is normal fuelling on a wideband S3 on factory power

<tuffty/>

 

[Machine212]

Ahhh nice, its a 2002 BAM.

 

[badger5]

std request is 0.95 lambda until 920c reached then it fuel dumps

yours is'nt that on the plot.

mapped?
logging on vcds possible? 001,031,115 blocks for example under wot in 3rd

 

[Machine212]

Yeah I can do the log. Probably not until the weekend though. Not mapped as far as I know.

 

[Machine212]

Its been a while but i need to revisit this problem, i did the logs you asked for a while ago badger. Hoping you have time to take a look.

 

[badger5]

its std... thats what it does until 920c is reached and it fuel dumps

 

[Machine212]

Hmm strange how all the other s3 runs on the computer he had to compare mine to all started dumping around 4k rpm. Reason I've brought this up again is because I've gone for another run with a mate with his Leon 1.8t and his dumped around 4k rpm too. Same dyno same conditions.

 

[voorhees]

All cars similar ? no intercoolers different ?

 

[Machine212]

Most of the one he showed me were making around standard power. Could my egt sensor be playing up?