[stephen low]

Trevor

Assuming without pictures but by your description the plastic pipe is indeed the fuel vapour return via a solenoid to the carbon cannister.

Not sure if it is for sound or air flow balance and I didn't try mine without the tube when the car was running but as I am running just a pod filter system the whole arrangement was noisy.

I really doubt that removal of the balance tube is really going to cause much elevation in noise levels unless you have the whole set up running ultra quiet and even then I'm not convinced there will be much variance.

Can you post pics of what you are describing for clarification?

Cheers