BMW Ionic Current Control Unit - Genuine BMW 13627834713

Detects knock and misfires by detecting the ionic resistance in the spark plugs, a common source of misfires and performance issues

Due to extremely high engine speeds standard knock detection places very special demands on components and system functions. Standard knock sensors are not capable of delivering adequate enough signals at high engine speeds.

On the S85 engine the spark plugs act as a sensor by detecting the ionic resistance during combustion. The ionic current control unit detects this resistance and "talks" to the DME to adjust fueling and timing to optimize performance. A failed ionic current control unit can cause a limp mode condition or a constant misfire in a specific cylinder. In order to determine the cause of the misfire a diagnosis must be performed first. The most common way to identify the issue is related to the ionic current control module is to swap the units from each cylinder bank and see if the misfire issue follows the control module vs staying in the same cylinder.

Please note: This control unit does not require coding. It is required to clear fault memory from the DME after installation of the new module.