In short,.. no
On a 3 plug ECU, spark advance/retard is controlled by the vac servo and the centrifugal weights in the distributor, much the same as on a carby engine.
The knock control unit simply retards the ignition in the presence of knock.
As you can see in the diagram, an ignition timing signal and a phase signal are sent from the ignitor in the distributor to the knock controller. If no knock is detected, the ignition signal is sent back to the coil unaltered through the ignition voltage wire.
If knock is detected, the knock controller adds a delay to the output of ignition voltage to retard the timing. Once the knock is eliminated, the ignition timing is gradually increased until it is back to normal.
Its the 4 plug ECU that calculates its ignition timing via inputs from throttle position, air flow and engine temperature sensors
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Last edited by Gannon; Sun 10th August 2008 at 03:31 PM.