buffer and random display characters (using u8glib)

I am using u8glib

I am trying to display battery voltage. Right now, i simplified to try to just display random integers

char bVoltStr[4];

is in a loop

What i get on the screen is (each line is an update)

3 4 9 some wierd upsidedown 3 some strange diagonal usidedown question mark looking thing 5 Z .....

I should only ever be getting integers. HELP please :)

I also tried (to eliminate font, position, lcd, and string buffer issues)

 u8g.setPrintPos(1, 26);

and get the same random, unreadable, characters