MK5 GOLF GT TDI 140 (BKD) Whistle on engine braking? performance issues.

[FrenchToGerman]

Hi all, having a few issues with my golf its the BKD 140 engine, basically its just not running smoothly at all and seems down on power. I have also noticed it makes a whistle noise when engine braking (only when engine braking) I'm unsure if this is normal?

It feels as if I really have to put my foot down before the turbo kicks in and it just doesn't want to go anywhere quickly. I have checked it over and I can't find any obvious issues but I'm unsure what to be looking for to be honest anyone have any idea what it could be?

car is an 08 plate and has 78,000 miles

[zollaf]

start with a code read.

[FrenchToGerman]

​Hi thanks for the reply, forgot to mention its not throwing up any codes.

[zollaf]

what it been checked with, proper compuiter like vcds or other high end machine or 30 bob ebay jobby. ?

[FrenchToGerman]

Was checked by a cheapish one of my mates, so would it possibly bring up a code if I got it on vcds?

[zollaf]

yes, cheap ones only checl obd codes usually, so next to useless.

[FrenchToGerman]

Ah ok i'll have to get the garage to check it, I was looking at buying vcds but can't decide if it would be worth it for how often i'd use it.

[zollaf]

depending onn where you go a garage will charge 20 - 60 quids. 4 goes and it could have paid for itself, or look on the vcds user map and see if there is a friendly member close by you can see.

[FrenchToGerman]

Yeah I see what you're saying, I may end up getting it as it would be very handy to have, I prefer to do my own work but it is a struggle when you haven't got diagnostic equipment.