ive been noticing a rattle coming my engine and it happens when i blip the throttle up to about 2k rpm i had thought it might be piston slap but on closer inspection it seems to be the boost solenoid rattling

is it normal for it to rattle ?

 

clicking???

they're meant to click

 

like a bad tappet ?

 

I had the same problem- couldn't figure out what it was and then had full decat exhaust fitted- in doing so had intercooler and turbo pipes disconnected to fit exhaust- noise stopped after this!!! Reckon a clip might have been loose on intercooler/turbo!!?? i.e. irregular pressure to boost gauge. Sounded like noise was coming from dash area!! My car is 2004 ver8 Sti.

 

If it is the solenoid, not sure, but have you checked the heat shield on your turbo, these can have a 'tinny' rattle to them which can be heard at lower revs.

 

i had also noticed that the pipes connected to the boost solenoid pull of very easy so maybe its due to a leaky pipe