Under bonnet pop on start up?

[Andy Pandie]

Starting up from cold this morning whilst in the garage I noted an under bonnet pop just before she fired, sounded like it was back through the airbox. I've never noticed it before, but also have a bit of hesitation around 2100-2400 rpm which I guess is throttle bodies, are the two related? Note I didn't have foot on or near the throttle whilst starting.

I am booked in at Str8six for a couple of weeks time, but was just a little concerned this morning. Is it something I need to worry about?

Cheers

Andy 'P'