JH I assume is a digifant engine right? If so get the static & ignition timing checked, this is usually the cause of sluggish digifants. Also worth noting that the ignition timing must be set to EXACTLY 6degrees BTDC at 2.25k rpm with the blue temp sender disconnected, otherwise it wont run right.
Also replace all your vacuum hoses with new stuff from VW, it wont cost much and is also a main cause of a sluggish digi engine!