In the quest to fix an intermittent hard starting problem as well as rough idle, I discovered that fuel was leaking from the AFPR when I took the vac line off the port. Seems as though this is a broken diaphragm in there.

My question is do I simply buy a replacement AFPR? Or do I need to buy a new diaphragm for underneath the AFPR? I'm not sure if AFPR comes with everything I need. Or if they're simply an adjustment tool for the factory diaphragm.

I see AC Delco has a # 2142156 that is listed as a replacement for my car. But it's just a spring and diaphragm.

 

Yup, that is the tell-tale sign of a perforated/ripper diaphragm. You just need the diaphragm vs new AFPR.

I don't know if any/all/none AFPRs come with a replacement diaphragm either.

 

All is well again. The adjustable fuel pressure regulator is really just a cover for the spring and diaphragm. The AC Delco part above solved the problem.