Nail in tire repair question
 

My tire pressure monitor warning turned on (no sound, just the light). Sure enough picked up a nail in a rear tire ('05 4.4i w/ sport pkg). I hope it can be easily repaired since the tires still have a lot of life on them. The event triggered a question though...

If I needed to do a roadside repair using the BMW system (with their sealant), assuming I had the system, would the gunk adversely affect the tire pressure monitor components? Anyone have any idea on this?

I have got the same spec car as you, I have had now 3 puntures over the course of 6 months (unlucky a) and all have been repair by my local tyre dealer, and I have been off roading with them too

I beleive the X5 tire monitoring is dependant on wheel RPM's mesured from the wheel hub, not sensors on or inside the tire!., so a sealant shouldn't affect the monitoring system, only the balance of the tire if the sealant were to settle into one position, rather than distribute evenly, which is why I advise against using any sealant for an extended period of time.

The more advanced systems like the one I have on my 7 series, to read actual presures, have sensors intergrated into the valve stems themselves and may be damaged by sealant compounds should they ingress into the sensor assembly.

BTW, I picked up a bit of scrap metal no larger than a 3" nail in the side wall of one of my tires a few weeks ago and the shop (Tyrepower Austraila) still repaired it safely and effectively without having to fit a tube., so even if the object is in the side wall it is still legal to repair it in Australia.