ad545i

<_< <_< MY2005 545i just get 369 miles then it posted error on low emission, service engine light cames out. I took to dealer to fix, they changed all the ignition coils.
The car ran O.K for couple of days, yesterday, there was a error message again, this time it posted high on emision, engine fault, caution to drive, then the service light came out, i checked on i drive's service message, it said error high on emission. Will take to dealer tomorrow. i don't believe that the 60K plus car got problem that early.
Any one the same problem like this before, please let me know.
Lemon law, if my car going to keep get same message after fixing, i think i going to talk to BMWNA for the replacement, What do your guy think?
Many thanks in advance.