Update query is being fickle

[JumpinJimRivers]

This is very odd and frustrating to me. I'm wanting to update records in my subform from my main form using an sql event after I enter a value there. LostFocus on the field I enter the value is the only event procedure that does anything and that even stops working once I save it, close and re-open the form. What's the deal? I've tried using a save method before the sql procedure and then requerying the subform afterword, and that doesn't help anything.