Shutdown moan at tank 2005

[Bikeflyer]

I have been wrestling extensively with issues on my 2005 reaching the 200k miles mark. It has historically had a random dislike of restarting hot, which then reared its ugly side when I replaced the fuel pump. It had leaking injectors. Replaced them. Replaced crank sensor, all ignition coils and plugs(copper) TPS, MAF. Cats are a year old, replaced a little early presuming the P0420/430 was that when O2 sensors didnt do it.

So, Replacing the fuel pump by itself boosted fuel pressure to 40s. Drops sometimes, sometimes higher. Determined the hard starting to have been when it was low into 30s psi. Then it started making a tim-allen esque moan grunt upon shutdown from the tank. Thought it was pressure regulator/check valve. Replaced the complete in-tank assembly. Moan went away for a couple days and came back the same time as the symptoms. Am I right in thinking the moan is a check valve issue, or something else? Not a whole lot of else left to do at this point.

 

[LibertyTC]

What brand of pump etc did you install ?
Fuel pressure tests should be key on at aprox 55 psi
Started & running aprox 60 psi.
Key off for 30 min reading aprox 45 psi.
A quality pressure tester was used for my tests.
Do you have a Mopar gas cap installed?

 

[Bikeflyer]

I have yet to see a 60 psi running number, just a vibrating needle at 58 peak. The current pump complete module was an amazon unit, Schnorkel brand. The previous motor-only refitted one was a bosch. It is not neccesarily a mopar cap, though I have never replaced it. Highest I saw key off with the previous was 45. Now 52. Harbor frieght tester. At this point I am almost tempted to add a permanent gage to watch it.

Additional symptom not mentioned, it has a 100 rpm surge between 1200 and 1900 rpm when going up a slow hill around 40-50 mph. Goes away outside that range and if OD is turned off. Been trying to quell that for a while now. Related? Intake manifold gaskets, IAC and PCV system are new. Cleaned TB.

 

[Bikeflyer]

Key off test is 20 psi after 30 mins, 56psi key on.

 

[Bikeflyer]

Finally got the warrantied fuel pump module installed. Slightly better pressure, still leaks down. Pulled the fuel rail with injectors attached. 3 of the china injectors from last year are seeping. Go fig. Got bosch units on the way.
The shutdown moan noise... NVLD pump. I put a spare on and sure enough it went away independent of the other noises.