Poor drivability with the engine warning light on.

The vehicle was in limp mode with the valvetronic system in fail-safe. Fault codes 2A61 (Valvetronic Adaptation) and 2A63 (Valvetronic Servomotor) were present, with 2A61 returning immediately after clearing. The engine had been replaced at another workshop a few months prior and had never run correctly since. The previous workshop had also replaced the valvetronic motor and sensor without resolving the issue, and a BMW dealership had subsequently diagnosed a faulty ECU.