[NoTempoLimitN54]

Get the 335is... you'll be glad you did.

I did a lot of research on this issue before buying my '09 335i. The HPFP installed after about March 2010 no longer fail prematurely. My original HPFP failed at 11k miles with the P.O. The current one has been working fine for almost 42k miles.

The story I was told is that BMW was getting ready to sue Bosch for all the trouble they'd had with the N54 HPFP. To avoid this, Bosch set up a new factory in Germany to make the new HPFP's and those new versions are the problem free ones.

Apparently the original N54 HPFP was made in China (no reliable sources on this info).

If the N54 was really such a bad engine, why did it stay in production 3 years after the introduction of the N55? And specifically why is it now only offered on "special edition (iS)" models and the 1 Series M Coupe?

The N55 is a better engine for the average BMW buyer. It has more torque at very low rpm, better fuel economy (Valvetronic) and lower emissions (one turbo = one pre-cat that warms up faster).

The N54 was an "almost M" engine that was detuned and put into various "normal" model BMW for a few years until they developed the N55. It appears that the new M3 engine will be a "super tuned" N54 development.