Running lean above 4000

[swarm]

Hi. I have searched, and havn't yet found my answer..

o2 drops to 0.00 @ WOT above 4000
air/fuel gauge reads very lean at this point (duh)

all stock


also, this may have something to do with it.. maybe

installed MBC.. no matter where i set it, it stays at 14psi...
so i unplugged the vaccum line off the wastegate and took it out for a careful drive... same thing, 14psi...


replaced fuel filter, coil pack, o2 sensor
car feels like crap when this happens... feels slower than a stock n/t =(

 

[Staytuned]

Fuel pump starting to check out maybe.

 

[blackGSX2g]

Watch the timing curve and see if its pulling timing. My car did that exact same thing, o2 looked normal till I went WOT, then it would read 0.01 0.00 0.02 etc. Timing looked fine and I knew I was running rich, so I just tuned to the timing curve and got soooo much more power and gained about 8 mpg out of it. Temp fix till you get a new o2 sensor.

 

[oddrob]

recheck your vacuum lines. If you lose the line to the FPR, the pressure will not rise with boost and cause a lean condition.

 

[swarm]

recheck your vacuum lines. If you lose the line to the FPR, the pressure will not rise with boost and cause a lean condition.

will do

also, in every gear, the turbo spools, pulls, then like... it's no longer there... turbo gone? no shaft play :\
maybe a crack in the housing somewhere?