Intermitant Under Boost
 

Cars only boosting to 0.6 bar. This happened the other week then it cleared, and the same the other day, and now today, but hasnt cleared today. Usualy boosts to 1.1/ 1.2bar. What pipes should i check for looseness? or what else could cause this? Cant understand it. Anyone shed any light on this?

No-one got any ideas, why keeps on boostin low then picking up after abit.