Engine service required

[mmarkcooper1]

Hi guys I own a xc70 d5 2003 model few months back I encountered the dreaded loss of power and engine service required etc, I suspected it was my front and rear engine mounts etc axle I was low on funds I uncapped both ends off etc and to my amazement it sorted it now its come back and plugged in obd dreaded torxpower one and identified it as boost solenoid a peirburg one which I got through work as I work fif a local factors input a new one on cleared the codes for thought I did from stone cold start booting her bright the faultback to current fault not pending ...today I took her out and did the same cold start floored her bam fault pops up loss of power except this time is solenoid fault pending with the engine warm etc I turned the engine off and back on faults gone out of reader and no faults when driving is there something addiontal I need to do to tell the ECU there is a new part fitted etc if I'm right in thinking that any help would be appreciated etc .