service engine soon light on 2003 BMW 530i

I have two different BMW shops run diagnostics on my car and they are saying two different things are wrong. What do I do? Service engine soon light is on.

2 answers
What is the diagnostic? Did they retrieved the trouble codes?
I got that message last night 2 minutes before the valve dropped into a piston. engine must be replaced to drive agin. 72,000mi.