so this past weekend ive been chasing a problem that just arose, light throttle a/f seem ok, but gets leaner and leaner into boost, where as it used to stay rich.

idle around 12.0 a/f light throttle/cruise between 12-14a/f starting to get into boost at low throttle it stays in the mid 12.s then just starts getting leaner 13s up into 14s into boost
if I just mash it at low rpm as boost is building it shoots right up into the high 13-mid 14s and stays there.

it used to stay in thie mid to low 12s when coming into boost <2psi , then go into the lower 11's in boost.

I was thinking it might be a fuel pressure problem so I replaced the filter, and swaped pumps with my other t2. no change.

then I noticed on the palm when maxing out the tps (its an s4 with narrowband) it only shows it at 94% on the rtek logger, I swaped tps with one on my other t2 and that only showing 97% as well. I did a run with no tps at all pluged in which I thought should make it default to 100% but it still did the same results. tps is adjusted correctly at idle.

could the tps not being 100% cause something like that?

cooelnt temp and air temp sensors all seem to be giving normal readings. as well

 

I think My tps only reads 95% or so at wot...do you have any exhaust leaks?

 

Have you rewired your fuel pump? or Bypassed the fuel pump resistor?

 

do you have a good vacuum source for your fpr? only reason i ask is that i had mine running to non-ported vacuum and the fpr wouldn't read boost and it would lean out in boost. maybe also check for vacuum leaks or a clogged injector?

 

Just wondering if you ever solved your lean issue?

 

Mine does that in the lower gears when I have less than 1/4 tank of gas, but, I know what it is.