Internal combustion engine combustion chamber spark plug condition determining system

摘要

The method for determining the condition of a sparking plug (Zk) is carried out with the sparking plug (Zk) in the secondary circuit of an ignition coil (Zs), arranged in series with a measuring resistance (R(mess)). For determining the leakage of the sparking plug across the ignition coil, a voltage is fed in the secondary circuit, which is insufficient for igniting the sparking plug. So that by a voltage drop at the measuring resistance, a voltage stands available, proportional to the leakage of the sparking plug. An AC voltage is fed in the secondary circuit of the ignition coil (Zs) and the voltage drop at the measuring resistance is filtered by a bandpass filter (Bp), and the filtered voltage after the rectification to DC, stands available as the voltage proportional to the leakage at the sparking plug.