You'll need to give more info. I went through a ton of testing to figure mine out.
First, when you say low flow, does it stop? A lot of times, the DC would be 100% but I'd have no flow being logged. I replaced, relays, FAV, pump, lines, etc. Same issue.
I would verify flow. I ran an extension line on the FAV to a clear plastic bottle inside my car. Went for a drive to verify flow. My dash lights never came on but I would get flow in the bottle. My case, issue was the c-clamp on the flow sensor.