A possibility is you have a sensor on the 5 V supply tree (orange wire) that has low resistance or is partially shorted. If the 5 V orange wire supply voltage is low it can cause a bus error.
One way to check (low tech) is to hook up a voltmeter to the orange wire at a good easily accessible position and unplug the sensors on the 5 V orange wire tree. I'd start with the sync (cam position sensor) then the TPS, then the MAP and then the oil pressure sensor, When the right sensor is unplugged the voltage in the 5 volt supply will come back up and hopefully, the bus error will disappear.
Check that the wires for the oil pressure sensor aren't chaffed and/or contacting ground, a known trouble spot.
I had a CPS that tested good but wasn't, it was sucking down the voltage in the 5 V supply orange wire tree. On a hunch I unplugged the CPS and my bus came back. Could be another sensor doing the same thing.
I'd check the cheap stuff before I'd do the expensive stuff. My standard troubleshooting routine is to test easy then hard, cheap then expensive.