Knock Sensor Function

The knock sensor used earlier has been dropped in the SFI system and knocking is now controlled on the basis of information received from the ignition discharge module.

The two induction circuits which sense cylinder pairs 1 and 2 and 3 and 4 are used for this. In the event of knocking, the ECM records one or more pulse spikes in the ionization current and, with the aid of signals from the crankshaft position sensor, can then make the necessary adjustments for the cylinder in which knocking has occurred.

Several parameters are adjusted to prevent the occurrence of knocking: turbo pressure, ignition timing and fuel injection time.