Can anyone help i have had a bypass valve fitted and after the install i now get a humming sound at low revs or on the motorway.
the boost is 16.3psi no fault codes and its not the usual cai whistle that you get. the valve has been calibrated and was tested before install.
I hope you guys can help.

 

please let us know the miles and mods you have

 

the mods,
quaife diff /webb 15% pulley/ddm cai/grs intercooler/janspeed header/quicksilver exhaust/ nitrostick cam/powerflex bush kit/motorsport developments custom map/colder plugs/top and bottom braces/ebach springs/pro race 1.2 alloys/
boost gauge/volt gauge/ scan gauge/rear seat delete/mini motorsport carbon roof spoiler
44000 miles on clock

 

was it a stock replacement or uprated? can you lift the arm of the bypass, is it smooth to do so?

 

It was a uprated one with a featherd edge to the butterfly and runs smooth.
could it be a leak

 

any other advice/help