It seems I have a very common problem, but have yet to find a posting with a resolution. My 2008 Mini S went to my mechanic with the familiar cold start problem,...it starts right up, but acts like its not getting enough fuel. There's no throttle response, and does a misfiring idle. If it doesn't die, I restart it a couple times and it runs great from then on. I just got it back yesterday with no codes, and 'ready to go'. I had brought it to mechanic 8 weeks ago with this problem, after I purchased the car a week before. He originally suspected low fuel pressure, or a problem similar to a weeping check valve letting the fuel drain down over night. Upon his inspection, they found a bit of antifreeze in the head, and went with the theory of it being a bad head gasket. Upon breaking down the engine, they sent the head out to be pressure tested. It was fine, but they planed it, and did a valve job since it was there. My tech then replaced all the timing components, thicker head gaskets, and reassembled.. Upon starting it, they found several codes of misfiring, and began chasing them down. So I now have new injectors, new coils, spark plugs, water pump, intake manifold, valve cover, and still have the same original issue!! GAHH!!! I've now spent more than I paid for the car and have the same issue. I do not want to take it to the dealer and have it tied up for months again, and spend another small fortune, or continue frustrating my mechanic grabbing at straws.
Has anyone found a working resolution?? Thanks in advance! ~Bob

 

Going through same thing....turns out it’s a bad fuel pump. High pressure side. Same symptoms as yours. Being repaired now and I will advise how it works ASAP. Pricey pump!!!

 

Thanks for the input! It’s been my fear that the pump is pretty common and may be part of the issue. Appreciate it. Please let me know how you make out!😉

 

Should get pump by Tuesday...I will post results probably Thursday...

 

New pump installed.....PROBLEM SOLVED!!!!!!

 

It WAS in fact my HPFP. So glad these forums are here ;-)
YouTube videos were quite helpful on the install. I had it done in less than an hour!