Methanol Injection

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For ECUs that support ethanol/FlexFuel, the ECT2 input may be used to adjust engine operation for methanol/water injection.


Hondata offers a wiring adapter for the AEM 30-3300 methanol controller to the ECT2 input.  This will switch the ECT2 voltage (and hence ethanol %) from one value to another when the methanol injection is activated, which is used to adjust fuel and ignition during the methanol injection.


The ECT2 voltage is approximately 0.65V when the methanol is inactive and 3.1V when the methanol is active.  Since the ECT2 will go to 5V if the adapter is disconnected this prevents ECU from removing fuel and adding timing under a fault condition.



Either ethanol/FlexFuel may be used or methanol, but not both.
Methanol injection requires less fuel and more ignition timing from the ECU, so a failure of the methanol injection components can severely damage the engine.
The installation and operation of the methanol injection kit is something that Hondata cannot support.
The setup needs to be dyno tuned.



1.Install AEM methanol kit and confirm kit it is operating correctly. A solenoid is recommended as it provides better operation. The nozzle size, controller start psi and controller end psi settings are documented in the methanol starting calibration for your vehicle.  If no starting calibration/modification is available, then use the smallest nozzle size to start with (generally 250cc) and set the start to around 7-10 psi and the end psi 1-5 psi higher.  Otherwise the nozzle size and controller settings are noted in the calibration.
2.Install the Hondata wiring adapter.  The adapter red wire is connected to +12V switched ignition power (which may also be the wire from the methanol controller to the solenoid) and the black wire is connected to the brown/white wire from the methanol controller.
3.Adjust the Ethanol Percentage table so that 0V = 0% ethanol and 5V = 100% ethanol.
4.Adjust the Ethanol Fuel Multiplier table to remove fuel when the ethanol % is between 40 and 80%.
Note this fuel value needs to be tuned on the dyno. Start with no fuel removed and remove gradually.
5.Adjust the Ethanol Ignition Multiplier table to add ignition when the ethanol % is between 40 and 80%.
6.Set the extra ignition values in the Ethanol Ignition Compensation table.
Note this ignition value needs to be tuned on the dyno.  Start tuning with no extra ignition and add gradually.



Start with no extra ignition and no fuel removal.
Add ignition 1-2 degrees at a time, looking for knock.
Remove fuel gradually, looking for knock.  Fuel may not need to be removed at all.
Retune if the methanol injector nozzle size, position or orientation is altered.