Have only just noticed a knocking noise coming from the engine area when I'm sat at 4k revs whiles driving but when I'm at a stand still and rev it to 4k there's nothing does anybody have a rough idea what could be wrong

 

Big ends.????

 

If it was the big ends would it not do it all the time ?

 

Could be the start of them but usually the noise would be there from 0 revs all the way through range getting progressively worse so perhaps not,
It could be anything tbh mate from wishbones knocking to suspension best bet is to either get up on some ramps take a look or go to a local garage and get them to take a look mate.

 

My sti is doing it...
Only starts at about 4k... Bit of piston slap..??
Best bet is find a good garage and have a full check up on it..
Maybe not.. Keep fingers crossed
Top mounts the list of checks are endless..!

 

Big ends are normally audable at 2500rpm as you release the throttle - would imagine its something on the drivetrain.

 

U only hear it when u driven and its def not suspension or anything like that

 

Have you tried the same revs in different gears to see if it is still there?

 

Just checked it there gaz and think it might be the box or something cause i only noticed it in second

 

Big ends usually knock worse on overrun from about 2.5k..Slap should quieten down when warm....