I think saltines give me severe heartburn
Why do you think they cause heartburn?
Because the pain goes from the left side of my chest to my back
Well, if you're convinced that's the case then you probably shouldn't eat saltines.  Sorry if you enjoy them, but you shouldn't be eating food that gives you heartburn.  Find a different thing to snack on!
It's alright, I'm going to miss these a lot less than my other diet changes
That's good that it would be a significant change to you. It's hard getting rid of something from our diet that we love.