need help or advice with engine tone

[tdh-syorks]

Not really a big problem as Clifford (my car) is running and drives really well, the slight problem is that when I'm driving steadily along, for example doing 30mph in 3rd the engine tone is bouncing up and down i'd say a couple of hundred revs. If I change to 4th obviously the revs get lower but this bouncing stops.
Under load the car pulls and sounds fine, I have no misfire whatsoever, its just when holding at around 1600rpm.

Could it be fuelling I.e injectors need cleaning or simply I need it re-tuning.

Many thanks Tom.

[hardchargin40]

Is it a WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM WHOM?   

[Ratty Pete]

Mine makes that whom whom noise.... Whats that then? Can never work it out!!!

[hardchargin40]

Charger.     

[Ratty Pete]

is it normal or something to worry about?

[Puncharado]

Normal.

[Justin14100]

its supposed to be some sort of g-lader resonance or something along those lines.

[tdh-syorks]

Its never done it before tho, I've owned a couple of G40's and they didn't either, I've had this one for nearly 3 years and its only recently started doing it, I'm gonna run it without the charger and see if I still get it.

Cheers guys,

[supercharged spaniel]

mine used to do it when ideling.