Only half boost with full throttle
 

The problem only seems to occur when I use full throttle in either 1st or 2nd, the next gear and subsequent gear will not go beyond 50% boost. So WOT in 1st means 2nd and 3rd only get half boost. I can reach full boost by only using ~80% throttle. Any idea, and the car is stock stanard.

check out this site if you haven't already.

http://www.autosportracetech.com/RX-...leshooting.htm

Per the link above, start with the Turbo Control Solenoid/Actuator:

"The Turbo Control Solenoid / Actuator is one of the more complicated actuators as it requires both vacuum and pressure to operate properly. This actuator is controlled by two solenoids, (both are wired together to the one ECU output) one solenoid applies pressure to one side of the actuator and the other applies vacuum to the other side of the actuator. With pressure on one side and a vacuum on the other side of the actuator, the speed of the actuator is improved. A typical problem is loss of Secondary boost in 1st or 2nd gear at 4,500 RPM, but reliable operation in other gears. This points to one side of the Turbo Control Actuator not getting it's pressure/vacuum, so it will still operate but not quickly enough."