Well after one year of ownership my 1.9 Tdi is having its 4 year service, by me and I was investigating (having done everything else)how to access the brake fluid reservoir in order to change the fluid.(which I’m not looking forward to)

A hose running to the turbo was obstructing it .I found if I prised a clip on the turbo side , it just pulled out giving me access.

It was then I noticed the flap and inside of the tube were contaminated with oily gunge.

I had noticed a slight hesitation on acceleration, and after the cleaning it seem to have sorted it.

Looking at various forums it seems this build up of gunge is not uncommon , if the vehicle is run a t slow speeds,

I wonder if anyone has any views on the matter. And is there any other parts /sensors that should be inspected and cleaned, as the engine is a complete departure from my old diesel Golf with its mechanical pump.

This is pretty normal. It's oil vapour from the CCV combining with the gases from the EGR.

Over time it will build up and reduce the effectiveness of the intercooler and clog up the EGR etc. It's a good idea to clean it all out every so often.

Thanks for the explanation.

Put my mind at rest, and will now clean out at regular intervals.