wai

I just installed the PLX wideband controller ,
my idle is shows " 14.6~15.5 , it looks too lean at idle.
when I WOT the car , it shows 11.7~12.3
I am running on stock boost too.
will leaking injectors cause running lean?

DigitalSynthesis

I have no idea about the idle mixture, not having fired my TechEdge wideband up yet, but hmm... 11.7-12.3 sounds lean on WOT, for the mods you have - at least according to what I've been told to tune for (10.8~11.2 at WOT). If you are running stock boost levels PSI-wise, but flowing more air, that can do the same thing, but again I'm not a turbo expert so I can't speak about that. However, I would suspect with a wider, more open intake and exhaust setup as you have, you will flow more air even at stock levels, causing the AFR to go on the slightly lean side without deliberate adjustment.

Basically, leaking injectors I don't think will cause lean unless they also don't open fully (which would be what causes a lean mixture... leaking only may actually cause rich and will flood the engine causing difficulty starting her), but the mods you have will. Can you not tune your fuel injection up a bit using your F-con? I am sure some others can tell you target AFRs at idle (a good friend of mine with a great TII was running high 12, low 13 at idle with a microtech setup), but I can only venture some general guesses to steer you hopefully in the right general direction. I'm waiting until my radiator gets in in a few days to start my first turbo engine so this is all based on my understanding of turbo theory.

wai

when I let off the gas , it jumps to 16.
I will try replace the fuel filter and see any difference.