I have a few symptoms, I think they're all related, just trying to narrow down how many things I should replace (probably all, but worth asking).

Symptoms:
Idle occasionally cycles from ~1300rpm to ~700 rpm, occasional settle to a steady 850
have blown 3 fuel pump fuses since rebuilding the engine, two in one day at the last autox
When idle is fluctuating, injector duty bounces from 5.5% to 0.0% in time with the idle fluctuation.

Car has 80k miles, engine rebuilt last year, about 3k miles ago. Have Apexi PowerFC with maps preset by SRMotorsports based on mods, DP, and cat-back exhaust.

Thoughts at this point are to replace fuel filter, fuel pump, and pulsation dampener. Any thoughts on if I'm on the right track or no?

(This should also get me to my 20th post, over the last 8 years, so I can post in 3rd gen forum next time)

 

My FC has the same problem with the idle bouncing between 1000 and 1500.