In message , Austin Shackles 
 writes
>The only place you normally get anything like "sludge" is in a vapouriser,
>it's called "heavy ends", and needs periodically to be drained.
And there's usually a nut on the vaporiser for just that reason.

For a lot less than £1400 you could get a complete new multipoint system 
on a 4 cyl engine.
-- 
hugh
It may be more complicated but is it better?