Octavia II vRS combi feeling "jumpy" when cold

Hi guys

First appology in advance already. English is not my native language, and when it comes to cars and motors, things get even more complicated, so honestly, I don't even know what to search for here on Briskoda to find possible answers to my problems.

My situation is, that my Octavia II vRS combi TSI (year 2011) is lately having some strange issues. First, it started to be "jumpy" when it's cold. First few km until engine gets to temperature and oil temperature gets to 60-70c or above, it feels like I would be sitting in cangaroo's bag not in car. Not constantly, but it gets few seconds periods (when running between 1500 and 2000rpm) that motor sort of loses power for really short period of time, then gets it back, loses it again, gets it back and so on (I guess this losing power is probably best description, even though I'm not sure if it really loses power). It just feels like it would be jumpy. I hope you know what I mean.

After a while, motor check light went on, and computer showed P2015 error (Intake manifold flap position sensor). Since it has 4 years guarantee (running out in 2 months), it went to service, and they fixed it. Well truth is, they changed intake flap (on first service they changed some metal looking part... yeah I'm not really car guy, sorry, and week later when light and same error went on again, they changed also that plastic part with flaps leading air to motor block) , they upgraded/changed software and light is gone now. Computer returns no errors, all is well... except car still feels "jumpy" when it's cold. Once engine gets on temperature it's working perfectly fine. Also fuel consumption is pretty much normal, and if you press pedal to metal it feels like it has all the power it had before. But I can't say this for sure, as feeling of car accelerating is one thing, putting car to dynamometer, test it getting real and exact numbers is another thing. And I didn't do this, nor I have chance to do test like this.

Anyone have any ideas what could be wrong with this? Thing is, I need to get this fixed in next two months, since I don't really feel like paying myself

Thanks for all the help, and I hope my description make some sense.

Primoz