P0172 /P0175 - Those are codes for Rich fuel trims, right ? I might suggest you get a BMW-specific code reader...the P codes are too generic..

These cars have no consistent problem in cold weather - other than frozen door latches that won't latch. I started mine and drove it to the airport at -1 degree F...and that's not even that cold...

If it continues, you should measure actual long term fuel trims with INPA or OBDFusion or other app/scanner. You might also measure your fuel pressure at rail.

We've seen bad MAF's, faulty fuel regulator in new fuel filter (Hecht) leaking injectors and other things cause a rich condition.

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'99 E39 528i 5-speed 130k
'06 325Cic auto 115k
'05 X5 3.0 auto 173k-SOLD
'03 530i - manual swapped - 430k miles-SOLD