Nice easy job - change the battery, that was until I lost one of the battery tie bolts down the engine bay.
So got to take off the intake [blitz] cones and under shelf. found the bolt but hang on, whats the other bit that has seemed to appear?
pics
It\'s a restrictor which fits in the outlet hose from the air pump, if you leave it out the car will "moo". Re-fit it and secure with jubilee clip.
Regards
Phil