Electronics from hell?
 

This is my first post on any forum.
I'm mechanically sound and I have read 100's of reasons why my Audi is acting up! I have searched and searched and for 1montj now I'm fed up!
I hope this is the right area to post!
I'm living in Sweden, bought my self a4 b6 1.8t

Everything is sweet except the turbo has a mind of its own.
I have checked and cleaned the MAF, cleaned my air filter, checked all the pipes I can for cracks.

I bought a diagnostic machine and one code keeps coming up 17536..

Which I clear and then the turbo might boost normally and sometimes it won't.

I think it is a sensor somewhere because the turbo will work after I clear the code sometimes which makes me think its not a boost leak...

So I clear the code, boost is normal then come to a set of lights and the turbo has died out. Today I tried switching the car off and then back on at the red light and the turbo worked again.

Please can someone give me any idea of what it could be!??
I've cleaned the MAF thoroughly, air filter is clean. Oxygen sensor( not sure if its same as MAF)

I have done a few other things to narrow the problem down also but can remember now!
Any ideas or thoughts would be really appreciated!
Thanks from SWEDEN

Any have any ideas?