need some help cant figure out why the power is droping when im driving my b4 i have a boost guage fitted and when the boost goes to about 1.1bar it drops down to 0.5bar and goes up again and it does this a couple of times when i have the boot down checked for faults and noting no engine light on or flashing checked all the vacuum pipes and doesnt seem to be any holes or slits could it be like a boost press sensor or somting like that out of interest what should it be boosting thanks for reading