Bicycle noise when pedaling
If you can diagnose exactly where the noise is coming from, it will be easier to know what you need to service/replace. It sounds like the squeak is periodic with the crank turning around (as opposed to the chain or the wheel), so that would suggest that it is a problem with the crank, bottom bracket, or pedals. Try inspecting and turning the pedals and crank independently and see if you can narrow it down from there. 

If the grease around the bearings washes out, the bearings can deform or break or become loose, and sometimes that will lead to a problem like that. Chances are the easiest way to fix it is to just replace whatever is making that noise.