I have a 2006 Cooper S which had the JCW kit installed around 60k miles. I took it in to get smogged, and it failed because they couldn't read some of the sensor codes. I took it into the dealership to check it out.

They weren't sure what's going on, but they said they had another 06 JCW with the exact same problem currently in the shop. The car runs fine and their weren't any other fault codes where they felt the car was unsafe to drive. They said worst case I'll need to completely replace the ECU/DME. I'm currently waiting to see what happens with the other car.

Has anyone else heard of anything similar to this? If I do have to replace the ECU, is there a good source of used ones? If I wanted to go ahead and get an aftermarket ECU program, where should I start looking?

TIA