Volvo 2019 VNL760 DTC codes

Does anyone have more information about the below codes? Best I got from Volvo was possible air in fuel system. Local shop said it's a 5 day wait to get in, 45 trucks inline to be serviced.

Symptoms...much slower accelerations under load and climbing performance is way down. Slight drop in fuel economy.

sa 16 dtc p 009b 13
Fuel Pressure Relief Control - Open Circuit

sa 16 dtc p 026c 00
Fuel Injection Quantity Lower Than Expected

mid 144 psid 247 fmi 14 count 1
Couldn't find anything

 

That's the funny thing, was replaced during recent PM.

Right after get filling up with fuel it started tripping these codes. Then noticed to water separator filter was getting dark rapidly. So then we replaced all fuel filters at TA and the engine seemed to smooth out a bit, although it didn't resolve the issue. Now the separator filter is dark again.

PS during that fuel stop, it took 15 minutes to fill up driver side tank, passenger side was normal.

 

I'm sure we did. So do we keep changing the filters until it clears up? Is this normal to change filters multiple times when getting poor fuel?

 

Already have gone through many tanks of fuel. Changed filters twice, water sep needs to be replaced again. Plus, oddly we are regenerating more often..

 

Idle is minimal. Since this fuel problem started, regen warning almost daily. Beforehand, rarely regen.