2008 GSX-r1000 Fuel Injectors Question

My 2008 GSX-R1000 has been dying at idle, no matter if it’s sitting still, or when i pull the clutch in and let off the throttle at speed. Thing is though, it runs perfectly fine at higher rpm’s. I attributed this to a possible fuel injector problem and ordered a rebuild kit, but when i pulled the injectors I noticed that 3/4 of the primary injectors are marked Keihin FVG17 but one is marked Keihin FBG23. Could this be part of the issue? Is there a difference? The parts manual says they should be Keihin 15710-21H00 which i think they are, but the markings are throwing me off.