Hello all!
i have a 16VT fiat coupe which i cant find out why running lean

specs of car:
Turbonetic T3/T4 ar.48 turbo
Siemens deka 630CC injectors
Walbro GSS340 fuel pump+wiring mode
front mount intercooler
2.75" downpipe and from there oem size (2.25" i think) all the way no catalitic
remus hardline rear exhaust
3bar fuel pressure regulator

and i have custom chip from KJ16

the car in boost is running lean, when start hitting gas i get about 10.5 at wideband and as long as i get high rpm it reach's 15+ at wideband

KJ is very good, and he told me i have problem in fuel since it cant be this injectors and setup and car is still lean

i have replaced all vaccum pips from MAP and AFR and no change
i had other FPR which i bought from ebay (also 3 bar) and i changed to him. the car drive 1 day with better fuel ratio
about 12.5 at almost all boost
day after it got back to lean.
i replaced fuel filter to a new one. still no good

does anyone have idea where i need to check?
i have order'd new MAP sensor from ebay maybe it will help?
maybe lambda sensor can cause thiS?

where should i go?
this wednesday i go to a mechanic that will check fuel pressure and i'll get a better direction. but maybe i can check somthing alse till wednesday! maybe i missing somthing

thankS!!!

btw. i have un-plugd the spark plugs to see maybe 1 or 2 from them is different color which mean injector problem, but all same

You can try the fuel pump wiring mod

ohh forgot mention!! wiring mod is already done :))

My guess would be either your fuelpump or your Map sensor.
Have you measured the fuelpressure off and on boost? If not do so.
If fuel pressure on boost actually is 3bar i would guess its your map sensor.
Is it an oem weber marelli?

hello. map sensor replaced to a new one.
and i think i found problem.
i had a vaacum hose that wasnt connected some how..
its the vaccum hose near the air sensor close to the map.
there is a plastic hose that comes from the rear. i guess from fuel pump area. i connected him to manifuld and the AFR was 12.5 on full boost. thats mean its good, just need new remap now


but a new problem came on.. last check on road after i hit the car the oil pressure went low and when car fully hot i up the rpm a slow up and i hear some weird noise from engine buttom like some thing got broken or loose. i think its bearing or oil pump. today i take sump off

That don't sound good!
Sounds like your having some bad luck with your car at the moment....
I think that is something pretty much EVERY 16vt owner goes through during ownership!!