I translate 'whenever' using subjunctive; ie. 'whenever you want' I would translate as 'cuando quieras'. I think this is correct, possibly it isn't.
I also use subjunctive for 'do y at the specified time in the future when x becomes true'. An example is 'let me know when you are ready', which I would translate as 'díme cuando estés listo'. I also think this is correct, again possibly it's not.
However this poses a problem for me when I want to say 'do y at the specific time in the future when you want to' (ie. for the condition 'x' I now use the verb querer). An example is 'let me know when you want to go', which using the same grammar as above I translate as 'díme cuando quieras ir'. But then using my translation for 'whenever', then this means more like 'let me know whenever you want go', which I feel like has a bit of a different meaning.
Can someone explain this to me? Perhaps these two translations really mean the same thing pretty much in English and I'm just over-thinking it