i recently removed the boost gauge from the pod so i could mould the pod into the A pillar. now i have refitted every thing the needle flutters when in vacuum at idle, if i increase the revs a bit the needle settles down, any ideas as to why its started to flutter? there a no kinks in the tubing or any leaks that i can detect.

 

I was told by a local motor sport shop, that it has something to do with the union on the back of the gauge. they recommended filing a bit off the end of the union to get it fitting better.
as it was a known problem..

 

Long shot but if there are no leak's or kinks at all maybe it's vabrations through the car, which are probably worse at idle. Rev it a little till the needle stops to shake, then tap it see if it does the same thing.