I am in Pauline,SC, about 80-90 miles up I-26 west from you, I have a new Clones timing set you can have really cheap if you want to try it. I think you are bypassing the one place I would look, the IP, if you had bad stuff that made it into the pump it would cause bad things inside it.

I also agree that you need to try and narrow things down and not just throw parts at it hopping for the fix.. Pull the codes, if you aren't sure how, say so and we will tell you how to do it.

A surging can mean several different things, you need to first see if there are any codes, if not, might try a new good PMD, not the cheap ones.

If you get stranded up this way, I might can help ya.