My sister bought a 1960's house with a crumbling brick wall which I
offered to fix for her - so first - I'd like to ask your advice.
http://www5.picturepush.com/photo/a/...g/12640783.jpg

The wall does not appear to be a supporting structure; and for the
most part, it appears to be sound - except a section under the porch
where the top few layers are crumbling apart.

Two basic question:
1. What would make the wall crumble only in parts?
2. What advice would you give me for a DIY repair?

Note: It's in a liquefaction zone - so I may need to reinforce it.

TIA