I have an 01 24v cummins all stock(I just got it) at 2000 rpms it it makes a loud whistle noise from the intake and power is low feels like a boost leak. I pressurized the intercooler and piping to 60 psi with some home made caps and pipes does not leak. The check engine light comes on and overboost code comes up. from what I have found it looks like it could be a bad turbo or waste gate. Any ideas???