So Basically this weird grunting sound has just started happening this morning,

Whenever i accellerate the engine has a weird sound to it, just in the first 3-400 rpm.
Not a high pitched tone, but a low sort of annoying buzz.

Any ideas as to what it may be? Or just book in to mechanic?

wow thats a new one to me. Grunting? Is it possible to write the kind of sound on here using adjectives?

Hahaha im pretty sure if i did i'd get lol'd.

basically i put my foot down, its accels fine, but it starts with a grumbling noise (no shudder or feeling from the engine that feels like somethings up) then after 500rpm just kicks back into normal sound

like its going to stall sound?

nah nah, Deep low tone then into the smooth accell sound

Exhaust leak?

ure motor grew to a v8 ?

could it be a vibration? Perhaps something is loose or collapsed. Does it do it in neutral/park?

is it this?

http://www.aussiemagna.com/forums/showthread.php?t=50491&highlight=grumble

if its a buzz sound its probably the cover on the exhuast where the y peice is. common problem

Mine has had a rattling/rumbling noise for months at about 1k-1.3k revs in gear.
Getting the timing belt done tomorrow and he's finding out what that noise is.

Was the drive belt, just needed tightning.