Hello. My name is Mark and I will be assisting you today.
It doesn't sound like you have any problem with your oil pump or oil pressure. Oil pressure should be 3.5 bar at 2000 rpm and you say the pressure rises a soon as you accelerate.
The tinney noise does need to investigated though.
Start by checking the oil level is ok. A low oil level could still show good oil pressure so don't assume because pressure is good that there is enough oil in the engine.
Low oil level could cause the timing chain tensioner to slacken off slightly and this could be the noise you are hearing.
the oil level is about half way, the pressure on the turbo gauge goes straight to 5 bar
calms down as i drive but increases quickly when i accelerate
I don't think you have a problem with your oil pressure. I made a typo error with the spec. It should be 3.5 bar at 4000 rpm.
Does the noise from the engine vary with oil pressure?
yes, the higher the pressure the more tinney it sounds, strangely sometimes when the engine has warmed up it sounds almost normal
there also seems a lack in performance as well
I think I would connect a separate oil pressure gauge to confirm the pressure. It could be a stuck relief valve but don't think this would affect performance.
Is the engine leaking oil due to the pressure?
Sorry Mark I was Offshore. There is no oil leak as far as I am aware and the level has stayed at half for a while.