Seems that its the possible cause for the absence of the overboost feature at 4000 rpm. In Europe, unlike the US, the HPFP is not covered by BMW, so im getting prepared for fixing it, rather than buying a new one!
they are pretty cheap now tho... in the US they have fallen to about 225.00, my 2 most recent customers were happy to replace them and pay us, rather than go through what the us dealers put them thru for the wtty repair
oh yeah...the local dealers will not do the replacement (per bmw/mini they say) unless it sets a failure code from the ecu AND starts poorly/won't start at all when overnight cold. So it has to have the code and be left there overnight and act up when they start it. When the pump was 800.00 eveyone was willing to suffer thruough all that and they would replace it if either the code or hard start occured. now it is both and with the total repair being under 300, many folks won't bebothered to be without thier car.