Coalman

Problem is getting very weird. To recap, I had an electrical failure in my 2003 E55 and supercharger would not work. MB brought in Tech Expert and he said electrical failure damaged ECU so they have ordered a new one, which is sitting in Memphis waiting to clear customs (So MB says).

Now comes the weird part. MB returns the car until ECU comes in next week. I take the car out and the supercharger is working fine. Dealer tells me he did nothing and we both agree we should proceed with new ECU since "spontaneous remission" may be temporary.

Is there anything I should know with the installation of new ECU? Have there been any modifications from original ECU in my 2003 E55 that will affect performance one way or the other?

Thanks.