I think mine does the same thing

mine is stock but the motor and turbos are new maybe 1100 miles on them



i went non-sequential and it is doing it now



i 'll go see demetrios (reactive racing) and find out what is wrong with mine maybe it is the same thing.

 

charge relief solenoid - valve

if your boosting 12psi on the primary...this may be the culprit...

the valve needs to close upon transition to provide for the secondary turbo boost