Sprake

Hi Guys
I ama after some help please, I own a 2004 E61 530d. i have had the car just over 18 months now and have had a few problem while I've owned it.

Over the past few weeks I have had an issue with someower loss, start the car from cold and it seems to run ok, ie the turbo whistles and it accelerates normally, once the car has had time to warm up theboost seemsto dissapear from the turbo. Have had the car into a local specialist and he reckons I need a complete new turbo, something in the region of £1500 fitted.

Now after trwaling through the forums I have found that it could be either the mass airflow sensor, the electronic turbo acctuator or the dpf. As I am reletively unknowledgable aboutthese sort of things, I am wonderingif anyone could shed some light as to what it could be?

Do i need a new turbo??
Also the remote keys have just stopped working (suspect tailgate wiring loom) and the alarm keeps going off at random times once its set.
Any help is gratefully recieved.