Hi Guys,
A lot of threads about misfires here. I am new with Mini. I acquired few months ago a Cooper S, 2012, 83000 km, manual transmission.

Days later I purchased the car, limp mode starting to appear (new for me). Bought a C501 creator scanner and gave me random misfires and misfires on 2, 3.
Changed coils and spark plugs. Life was good for a week. Misfires/limp mode again.
I searched for possible leaks. Notice an important crack at the suction pipe to the turbo. Fixed it and it last another week without issues.
Bought pro line Liqui Moly for cleaning the injection system. No change.
Misfires appear after half an hour approximately of running and under almost no load in the gas pedal. High revs works fine all the time.
Reading here and there, I installed a Mishimoto oil catch can.

BTW, misfires is mainly random, but sometimes it is more on cylinder 2 and/or 3. I reset the codes and life is good again for certain period. I have to drive with the scanner on, to erase the codes while driving.

Next step is looking for potential problems with the HPFP. The scanner shows different behaviors during idle. Sometimes I can see stable 5 Bar on the rail, but sometimes big fluctuations from 1 to 11 Bar at idle for quite some time, then it stabilizes at 5 Bar. It is a random behavior, either cold or warmed. Please see video.
Is this fluctuating pressure causing misfires?.
Bad rail pressure sensor?
When the limp mode appears, I noticed the fuel pressure has not dropped.
Does the limp mode causes misfires too in order not to over stress the car?. I do not know what is first, misfires then limp mode or limp mode for xx reason then misfires? (chicken or egg situation?).
Can we get rid of the limp mode?. I erased the misfire codes and it works perfect so it looks the problem is instantaneous and should not damage the car.
Next step is searching at: carbon at inlet valves, fuel filter, more leaks between MAF and throttle body, throttle body itself, etc.

Thanks for any comment