USA RB25DEt problems

[97'240sxSE]

Hello I live in the US I have an RB25det and i need to know if anyone has had a problem similar to mine so i can find a direction to start. The RB motor is not reving past 3000 rpm. It pulls hard until it hits that mark then it dies off. It doesnt die it just stops building boost. Ive check the obvious IE boost piping, maf, and waste gate i was wondering if any has had a similar problem.

[GTRgeoff]

What car is the engine in and what engine management are you using? It sounds like limp home mode where the factory engine management protects the engine. A few more details and I'm sure the forum will produce an answer.