This might be of interest to you all - my friends car is over fuelling. It has been mapped by a reputable chap and was until recently running spot on 12AFR when on WOT. Boost pressure is either 1.2 BAR (low) and 1.4 (high).
Summary - 12AFR before, nice
![Very Happy :D](./images/smilies/icon_biggrin.gif)
10.5 AFR after, not nice
![Sad :(](./images/smilies/icon_sad.gif)
We have used the same rolling road for all the results below by the way -
this was when the car was running nicely. The only changes to the car have been a single peice propshaft, and a change of exhaust to an apexi n1 evo (used to be a 3" system with 4.5" back box-no issues with this just wanted a different sound)
RR last year setup nicely
http://i161.photobucket.com/albums/t203 ... A61347.jpg
The RR resulted after those two changes is this.
low boost
http://i161.photobucket.com/albums/t203 ... A61349.jpg
high boost
http://i161.photobucket.com/albums/t203 ... A61350.jpg
compression tested the engine 140,135,140,140
boost leak checked the intake system up to 20psi the system is spot on.
Sure enough, logged the run out today with the car and looking at the fuel map, as soon as it comes on boost, it starts accessing the last or second to last column TP load.
The AFM was suspect but we have looked at that and Nistune shows it is producing the right results up the rev range, no anomalous readings.
Surely a proshaft and exhaust change shouldnt cause such an issue?
Results on a postcard if you can, I will attach the datalog for anyone that is really looking into this.
Thanks for any suggestions!