All started after i exchanged crankcase ventilation. As many may know, that this fix is pain in the ass, and there is lot of vac and electrical cables in the way, so maybe i think i have messed something up, but lets start from beggining.
So i replaced crankcase breathing valve because i was having lot reving from 800 till 1000 in while idle, after this was done it started to work normal and kept 800rpms.
after some day driving engine check light came up and i got code G79/G185 implausible signal. I took it to mechanics and 4 from 5 told me that i got to change throttle boy. Electric said that it can be wires, connectors or the pedal assembly. All i done at that moment, i deleted codes, did tbp and all was fine for some 4 weeks, after then it came up again, this time with EPC light on (Limp mode) and what was strange i started to expierience problems with brakes, when i was pressing brakes while idling, the rpms slightly went up to 1500. (same faul code)So i did 1 more time code erase and tbp. After that all problems went away. Drove for one more month. (Wasnt really fixing it because i was waiting for warmer time to check everything, because i didnt wanted to start pay big $ for new parts just to find what is acctually gone bad) Yesterday i drove to work and EPC came up without engine check. This morning when i tried to get back from work, EPC was still there and engine check light joined the party. So after couple metters i lost any response from accelerator pedal,engine was idling normal, no hard idle no nothing just wont accelerate. Turning off and on engine, didnt helped, so i took off battery + for 10 mins to reset ECU (had to get home somehow and there wasnt unicorns around
). So it started just fine, from work to home is some 20 miles. Had to stop at red light like 300m away from home, then i lost acceleration again, but this time i was able to remain movement in speed around 2mph... At this point i understood that it is almoust 100% that this is actually a pedal assembly, (this time i dont have codes, because i took battery power off). Next problem was to get pedal assembly, as i m living in europe, but the ATW engine ir for US exports, in my country no 1 has replacement for that part number. So i found 1 and only in scrap yard. Seller wanted 40$ for it but i bargained it for 30$
(Told him that it is his last one of that kind so he must be lucky that i m buying it, after i got that pedal, i told him how rare actually this part is, he started to look at me with angry eyes, so i guess it was wrong thing to tell him that, because he understood that i got it for way to cheap) 
But i had the assembly and exact zero % shame 
Went home and replaced my pedal assembly, what was serious pain in the ass and in the right hand (still hurts) as i m currently without my wag com, i was not able to do a check, all i done to readapt, prior replacement i disconnected battery and after i fitted new pedal, i reconnected, so the ECU had to restart. All was fine, except 2 things... 1st is that brake problem is back it starts to increase rpms while i presson brake, but there is one more thing now, i tried to put car in Cruise Control while i was preforming test drive, it didnt respond, the car was like kinda jumping, then epc light came on and i lost acceleration again, after turning of engine and turning back on, epc disapears and i got acceleration again, then when i tried again same thing happened. The car is DBW so i guess vaccum leaks may cause breaking problem, but not the CC.. Son now i m dunno, is those two thing connected or what? :O tommorow i will do a vagcom scan and will search for codes. Also, i havent done TBP yet, may this cause those problems. My only version (actually i m noob on cars...srsly a noob) that if there is not performed TBP (Throttle body positioning or adjusment), CC wont kick in because TB is not working properly so CC control module is having conlflict between sensor data, and also i guess it may cause reving problem because of wrong amount of oxigen in intake manifold? :O I m not sure if this makes sense, but i hope there is somebody out here with some recomendations what to do. Web is full with similar problems, but the problem is that, no 1 after fixing issue update info on what was actually the problems cause. My small issue is described in amount of independence declaration, but i help it will help you to come up with some bright ideas because my crystal ball is bit cloudy...Car specs:
Audi A4 year 2000
Face lift D2B5 sedan
1.8t ATW engine 5v20 DBW
mileage is near 300000(KM)
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