Thank you for the feedback. I looked my CCV pipes and it seems that they have been replaced 5 years ago(two separate pipes now, the production year is 2011). The pipes looked fine, but the connections did feel a bit loose, but it can be because of the how the connection is sealing with only one o-ring. I will try the electrical tape soon.

If someone has INPA available during the morning cold start in freezing temperatures, I would still be very interested in the valve lift numbers. Just to eliminate any problems with valvetronic control module.

I did have it on first thing a couple of weeks ago after my first case this season and it (valve lift number)was all over the place , it kept changing like totally variable, Will give it another go one of this days when temps fall and keep you posted.

I tried the electrical tape isolating method today. I isolated three connectors with the tape. The fourth one that is the lower connection to the inlet was not isolated because I could not fit my hand in there. Unfortunately the results were not showing any improvement even though it did not misfire. The reason is that temperature today was at least 3 degrees warmer than yesterday so based on my previous experience this temperature difference will be enough to help engine stay out of misfire error.

Here is a video from today after the "electrical tape tuning": https://www.youtube.com/watch?v=0nLpg59xWxE

The car is completely cooled down, it is 3C outside. The valvelift again goes directly to 0,3mm from start up and very rough idle appears. After some time it stabilises at 0,4mm. The value is actually set to 0,5mm in INPA. I checked the value later with warm engine and then it was 0,5 mm like I had programmed it. I really would like to know what is the logic behind the decisions valvetronic is making. For me it seems like when the engine is warm, it will go to the predefined valvelift right away. When engine is around 10 degrees celsius, it will set valve lift to 6mm and keeps it that way for about a minute until the valvelift drops to the set value. When the engine is completely cooled down, it will go directly to the set valvelift, just like with warm engine.

After some driving today I reset all the adaptation values for the engine and set the valve lift to 0,0mm. The idle is fine right now, but when I put gearbox to "D" and hold brake, the idle starts to shake a bit.

Have you checked for codes? I skimmed posts and don't see where you've mentioned doing so.

My interpretation of this thread is everyone is trying stuff to see what happens without knowing what variations are acceptable and what should happen as it warms up and why. Very bad idea. Further, drawing a hard and fast conclusion from research or otherwise is always unwise without troubleshooting verification.

In the vast majority of cases making these adjustments are a bandaid at best. I suggest troubleshooting other far more frequent causes for this type of problem such as the secondary air pump, vacuum leak, air/fuel controls, etc.

I have checked the codes. The only codes that come up with engine are secondary air pump related P0491 and P0492. I have read tons of threads about them and as far as I know secondary air is guided directly from the secondary air pump to exhaust ports to heat up oxygen sensor and catalytic convertor more quickly to lower the emissions during the cold start. In my mind it has no effect on the engine during the cold start. Or am I wrong here? The car has almost 300000km on the clock, so clogged secondary air ports are very likely the cause of these codes.

Anyway, during the holidays I did some highway driving and covered around 700km after reseting all the adaptations etc. Since the weather has been around 2-6 degrees I have not had any misfire problems during cold start ups, but I have been getting jumping revs (700-1100rpm) after cold start that begin about 10 seconds after the engine is started. They last about 10-15 seconds and then everything settles down withoud further problems.

I also bought a new oil filler cap just incase and tried to see what happens when I pull out the oil dipstic while engine is running. After doing it, the engine lost revs immediately and felt like it wanted to die. Also, it was easy to pull it out, no exessive vaccum in the crackcase I guess. After putting the dipstic back, everything was normal again.

Today I had a chance to film the car start up while there was 2 degrees outside, but the car had not been driven for 10 hours, so the engine coolant temp was still 6 degrees. You can see that during this start up the valve lift is set to 6mm and after the engine warms up a bit, the valve lift goes to the default value. No misfire, no major jumping revs this time.

https://www.youtube.com/watch?v=N9J1R6eejs4

Secondary air pump runs for about a minute during cold starts. If failing, sometimes you will hear a knocking sound and a whirring noise. The knocking noise is gone is a second or two the whirring noise lasts for the time it runs. A malfunctioning pump will cause missing during the time it is running.

Could you explain a little bit more about how blowing air to exhaust change the way engine is running during the cold start? I would assume that the oxygen sensors are not reading during the cold start anyway, therefore, only increased/decreased backpressure could somehow change engine behavior.

Just to add my experience my endings has only 119000km on the clock and my cold start issues are totally random only common denominator is cold ambient temp (freezing or close to it) and it seems to more likely to occur when engine has not run everyday and /or when my gas tank is below half.....
I have noticed that when I removed my throttle bottle some time ago there was a fair amount of oil in the intake, could that get worse when car is parked for several days?,and have an impact on the cold start issue?
Just am puzzled and have been trying to find root cause for several yrs now..

The misfire is there until the engine is in closed loop operation. The secondary air pump causes closed loop operation to start sooner by increasing the O2 which results in faster heating of the O2 sensor and cats. If it is the pump you should hear a whirring noise or grinding type noise for a short period of time after a cold start. It could be other components of the system rather than pump itself. Suggest you check for error codes.

BMW Secondary Air System Fault Code Diagnosing How To DIY OBD-II | Bavarian Autosport Blog

Just posted two videos on YouTube showing my set point readings, idle when cold is.80 as well as when driving and not accelerating.
When accelerating it increases substantially.
Also worth mentioning is that after resting the engine for half an hour and upon restart the set point is @6mm.

Unfortunately it has been not too cold recently and this morning when I took these readings it was barely above the zero mark and yesterday when I did get an SES light and cold start stumble with faultcodes again at similar temps.
Hope this helps.

https://youtu.be/6F4W_n2AMdM

https://youtu.be/pld67Ostcy0