High pitched squeal.

Hi all I have a 57 plate freelander 2 td4 diesel my problem is a high pitched squeal on decelerating and sometimes on acceleration. I recently had to replace the throttle body and the front pads and discs. The car has now started to blow out black/blue smoke and feels like it is being held back in the power department and has started donkey on set off. Anyone have any ideas what this could be.

it could be turbo tubes/pipes especially with black smoke

Check intercooler hose for tiny split etc and all vacuum hoses, also egr is working if not blanked off.