Ecutek tunes dont fool readyness monitors npr does any tiune system i know of fool readyness or alter them.
If you disable a DTC code in a tune to stop a cel light it doewnt set the readyness to good it jist stops cel code.
Often disavling the cel may prevent readyness from ever passing.
Flex fuel kits generally hijack the evap pressure inpit or the rear 02 senspr input ant therefore will stop readiness monitors from completing and getting to pass
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