this engine fuel pump prassurae low. it fuel pump celan. Your problem sovel
If wiggling the wires cured the code, then one of the wires is broken inside the insulation. Pull on each wire one at a time. look for the colored insulation to stretch, this will be the broken wire. For the other car that wont rev up, this is a common when the catalytic concverter is plugged up. This will also cause MAF codes, and in turn, TRAC OFF light.
Anytime a bike sits for that long you stand a chance of fuel system problems. It sounds like you may need to "boil out" the carburetors and of course resynchronize them with vacuum gauges when you put it back together. You can also use a mercury manometer for synching the carbs. My guess is you have varnish still in the float bowls that is causing erratic running and perhaps the vacuum operated slides are not working correctly.
Offhand and initially, pls start by referencing the steps as outlined here.
Hope this be of initial help/idea. Pls post back how things turned up or should you need additional information. Good luck and kind regards. Thank you for using FixYa.