S5 t2 stock everything except

*rcinjector 720 primary and secondary

*255 walboro

*aem afr

*ecu rtek 1.8


At idle afr Is 10.5-10

And on top end it climbs to afr 13-16 all around


Car shoots no smoke and shows no sign of hesitation


Any idea why I'm goin lean?

 

o2? tps? afm? whats your fuel pressure on boost?

 

02 sensor was replace
I have stock fuel pressure regulator

Afm I switch wit a friend of mine n still reacted the same

Tps not sure on dat

 

fuel filter changeout
also check fuel pump for dead head pressure test or flow rate test , may need replacing,, may need a bypass relay

 

yep and try get an aftermarket regulator

 

fuel filterus new

Ima check fuel pump tmrrw............




I have a vortex fmu but don't know wat ratio it is

 

if your leaning out at high rpms with your setup, its most commonly the fuel pump. Either its going dead, or its not getting full voltage at high rpms. Also, be weary of chinese knock off walboro pumps. I had one from previous owner and the flow died out at high rpm.

 

Be sure your AFM is the correct part number. Should be N370, N390, N3A1. anything else won't work.