scooby_wrx_19

hi i thought i knew quite bit bout scoobys well my latest 1 is testing me,
i have a 94 wrx with apexi filter, front mount, z4 ecu, this is how i bought car

right check engine light comes on, code 24 idle valve. and 44 turbo pressure
cant get past 0.5 bar it just tries throwing me through windscreen, and the revs are up and down.
so replaced idle valve, turbo, maf sensor,map sensor, boost solenoid, all air pipes, still same so replaced ecu,

now this cured it for a week i could get up to 1 bar, engine light still came on a week later it has happened again i cant boost past 0.5 and same codes have poped back up, cleaned boost solenoid and idle valve still exactly same.

i know ecu hasnt been mapped to my car but it ran ok for week with the z4 ecu
reading the other threads about boost probs and i thought remap is answer, so i replaced front mount back to standard and changed ecu again and still wont boost past 0.5.

i appriciate any help hopefully some1 has had same prob and can help.