I was also thinking the same thing. But driving around with only the EFI running, it still did the herky-jerky, so I'm not convinced it's 100% the issue, but I would agree it's likely a significant contributing factor.
I looked back at the datalogs from driving with the EFI, and at no point did the RPM signal ever quit, fade, or drop out. So I am more convinced it was a failing fuel pump.
If it wasn't the fuel pump, it's ~possible~ that my bins aren't separated well enough and the O2 sensor is over-reacting. But manually tweaking the VE table wasn't finding a solution either. No matter. I need to make another car my daily so I can spend more time sorting this.
In the mean time, I have more alternator than I've ever had now
