My 07 MCS has been acting up lately. Twice in the past week it would refuse to start on a relatively hot engine (about 30 minutes after driving), it would just continuously crank and does not fire as if there is no fuel and spark, then I get the "engine malfunction - reduced power" fault on the gauge. On both occasions the car was towed to the dealer and as soon as the car rolled off the truck it would start normally (no sputtering, solid idle, boost engages etc..), codes are gone and there is no trace of logged faults. The first time it happened we thought it might be a fluke but definitely something is wrong as it happened again.

Car would start fine every morning/cold engine, no hesitation, no boost cut, idle is rock solid, no sputtering, revs well... in short everything is perfect. Battery is relatively new too.

Can this be symptoms of a dying HPFP?

Need help... I don't want it to happen again.

 

More than likely.

But first, grab hold a Bavarian Technic scanner and see if there's any current fault codes.
If codes are inconclusive, time to test fuel pressure both out of the fuel tank and into the fuel rail.
A low or varying pressure is a tall-tale sign of a dying / failing fuel pump.

- Erik