OK i am truely puzzled i have no clue what this could be...



Details on car

87 T2 w/

moderate street ported s4 t2 motor

Rtek 1.7 + 720cc injectors

walbro 255 fuel pump

3" ehxuast and 3" intake.

ported waste gate on stock turbo.

emissions removed. ( and no 02 sensor wide band currently in place for testing)

NGK AFX wide band

Autometer boost gauge.





OK so if i barly give it gas around town it runs fine air fuels seem to go fairly rich at real light throttle 12's and then around 14-15 around light throttle ( which is fine with no o2 sensor)



BUT if i try and get on it ( 1/4th throttle or more) at say 2500 rpm or more it either stays lean and starts bogging/missing as i aproach boost( like -5 vacume or so) and af will peg out my wide band at 16:1



or a/f start droping down like they should for a second or two enuf to make it start spooling good and i get into a few pounds and then the a/f start leaning right back out toward 15:1, and then it starts missing/bucking/detonating/god knows what again.



now i know a miss will show a full lean but the a/f is quite lean before it starts missing it seems like the a/f just dont seem drop down like they should when getting on it.



ive replaced/swaped or have tested

fuel filter

had injectors flow tested

rtek 1.7 ecu

air flow meter

boost sensor( stock gauge works fine, ive done a test with no boost sensor same result)

air intake sensor

water temp sensor

TPS

leading coil pack

fuel pump + checked voltage and wired pump for high voltage at all times.

new spark plugs bur9eq all around.

checked timing



now ive tried getting on it for a few seconds at higher rpm like 4K and it gets quite lean as well and can bog hesitate ect at a/f around 14's going into boost (SCARY!!)



im worried im going to blow the motor so i need to figure out what this problem is



Could the street port cause such lean conditions i would think the AFM would see the increase of airflow and compensate??



im puzzled any input would help.

1. is the fuel pressure regulator hooked up to vacuum AND boost?



2. do the secondary injectors work/turn on?