vauxhall gearboxes are worst than imprezas,
The late Cdti egr sysums always fail, can make noises when the pluger inside gets stuck with carbon diposts, the plunger get stuck 1/2 open when it needs to be closed then you get a noise witch sounds like loud turbo spool, can also stall and throw the eml on.
really need to listern to the noise rather than guessing at the common faults
tone