Mysterious laptop condition-not turning on right away

I have a Dell Inspiron 15r, Intel core 7 with a 1 terabyte memory I got last September.

Until recently, it started acting up, after I spilled iced tea on it. 

It was working fine for a few days, I let it air out but made no notion to clean it thinking it was fine because there was not any sugar in the tea.

Now my laptop is having issues. Some days it will start up fine, and other days I will have to take the battery out and wait several minutes to a few hours for it to work properly again. The light that tells it that it's on lights, then goes out right away when I take my finger off of the power button.

I don't know what the problem is. I'm hoping it's something like the battery is bad, but with my luck that would not be the case. And the Dell Diagnosis is not working on the computer no matter what I do.