Hi Nelly.....Yep balance was done with the air bleeds closed. Its just that I cant remember it being this far out the last time I did it. Had a good look around and couldnt find anything wrong. Checked belt alignment and tension, Compression test was in balance, Changed coils and leads over, new plugs, changed injectors over all to see if it made any difference, but didnt.
Couldnt find any leaks in induction side or any leaks in the exhausts. Just seems a bit odd to me.
As you say, co balance is the most important, so it is set now, just got to take it for a road test to see if its all ok.
Just another question. Is there an offset in the rear cylinder fuel mapping on this (st4 2001)?