Confused! VAGCOM error 00575 control limit not reached.. but now its working again? 2.5 tdi AKE

Hi,

So, im confused... yesterday my car decided to be completely gutless, like limp mode... but now its working again! ive done as many tests as i could think of, sorry for the long description, but VCDS readings and vacuum hoses moving actuators dont make sense to a total car noob like me :)

When there was a problem i saw the following:
1. MAF reading was always around 400, +/- 10 no matter what i did
2. basic settings 011 to test turbo actuator - the actuator would move but not very well, it would go to the top and then drop down a bit, like a vacuum leak. exhaust note didnt really change.
3. I can move the actuator with my hand, seems to be free moving as it should.
4. basic settings 003 to test EGR MAF reading didnt change at all.
5. tested MAF with multimeter, was reading 1.7v at idle, up to about 3v or so when reving it up. wasnt fluctuating.
6. intake pressure actual reading was around 1000mbar, wouldnt really change at all.

Fixes i tried:
1. checked for vaccum leaks as best as i could, found some of the 3.5mm braided hose which looked "a bit ****" from the n18 valve. replaced all of that, but still the same problem and same symptoms test restults as above and crap performance.

Now all of a sudden the car is running find again.
1. boost log showing actual intake pressure is boosting properly as normal
2. maf reading is now showing correctly and doesnt stay at 400ish
3. The turbo actuator now moves right to the top and holds there in the basic settings actuator test and i can hear exhaust note change when its cycles on and off.
4. EGR is now working and i can see MAF reading fluctuate a bit as it opens and closes.
5. after it was working again, i did try disconnecting the MAF and then testing the EGR and turbo actuators and both still moving correctly now even with MAF disconnected, cant be the MAF.

So what the hell is going on? :)
Could it be the N75 sensor thats intermittant faulty, would that cause all of the test results I described above?
I assume it cant be a vacuum leak as that wouldnt fix itself surely?
Also when the fault did start yesterday, it was running fine on my way to work, then on the way home, instantly down on power.

Hope someone can help, not sure what else i cant test or look at lol.

cheers!