You can adjust a range of settings in regards to knock control and the parameters that can be monitored (Under Knock Control in the entity tree in MEITE):



●        Enabled - Controls the ignition and fuel trims, knock readings will still work even if set to ‘No’.

●        RPM Min/Max - RPM range in which the knock control to act.

●        Max. retard(deg) - Maximum number of ignition degrees to subtract from the advance number when knock is detected.

●        Rots. / retard step - How many engine revolutions before ignition is retarded by ‘Retard step (deg)’ when knock is detected.

●        Advance step (deg) - When knock is no longer detected, how many degrees of timing should be added back for each step.

●        Windows start (deg) - Not used for now, knock window starts with ignition event

●        Window len. (deg) - the duration (in crankshaft degrees), after the start of the window, during which the ECU listens for knock. Known as “Knock Windowing”.

●        (Reset) Time constant (us)  - Admissible interval is 40 to 600 us

●        (Reset) Gain - Admissible interval is 0.111 to 2.

●        (Reset) Band-pass frequency - Admissible interval is 1.22 to 19.98 - The engine-specific frequency which should be used for identifying knock. Signal processing will be done to only keep a narrow frequency band around this, the rest of the signal being ignored.


Warning: Settings marked with (Reset) require a power cycle of the ECU to apply the changes to the DSP system.


There are several 1D tables that also specify how knock operates. These are:


Knock Acc. Val Table - Determines the acceptable knock reading according to  RPM. Should generally decrease as the RPM increases.

Fuel Knock Trim Table - A simple multiplier to add fuel when knock is detected

Knock CLT Scale Table - A multiplier to modify the acc. Knock reading depending on temperature.

The outputs of the knock module (which can be viewed as DROs) are as follows:

Knock Status - Current status of knock control module (Disabled, No Knock, Outside RPM, Max Retard Ign, Retarding Ign, Advancing Ign)

Knock Reading - The live value read from the signal processing module. This will decrease with RPM. Because the window length is determined in crankshaft degrees, its duration (in milliseconds) will be lower as the RPM increases (60* is 8.3ms at 1200 RPM, but only 1.66ms at 6000 RPM). As a result, the “accumulated” value (which gives our reading) decreases as well.

Fuel Knock Mod & Ign Adv. Knock Mod - Shows modifications done by knock control to fueling and ignition

Knock Lvl Rel - This value is obtained by subtracting the current Knock Acc. Val from Knock Reading. If it’s positive, knock was detected.