Jasonlo

I guess because 450 doesn't have throttle body, which can smooth out the diesel engine shut off.

Besides the pressure hose going into the wastegate actuator. there's a corrugated cable. It looks like this cable going into the air intake pipe after the turbo( not so sure). Wondering what is it? Air temp/ pressure / mass sensor?

have you done a compression test on the intake side? pressure it up to 10 psi, listen for hiss.. boost leak is common