Sorry for you. Have you checked the ECM relay? There are a lot of test to do before putting a diagnose like bad ECM. I hope your mechanic knows what his doing.
I once was trying to find the issue with an E38 which was not starting. 2 other mechanics say that is bad ECM. Car was not starting often and without any reason. It took me a lot of time to test signals from ECM. Sometimes were working sometimes not. Finally I found out after a lot of hours spent that the weather seal from the windshield was damaged by the sun and it was letting water to drop on the cables and then in the box where the ECM is. It was not necessary to rain outside.This happen when the humidity was high in the air or when washing the car.
Anyway I wish you luck with yours!
Last edited by joyism5; 02-17-2011 at 10:42 AM.