If the injectors are clean and the fuel rail is flowing properly then you're down to either a fuel pump issue or sparking problem. The idle is set by the fuel injection system and ignition timing circuits in the ECU so it's not like dorking with a carbed system. I had some bad gas in my Gen 1 Rocket and the fuel system idle adapted to the bad gas and I couldn't get it to even start until I cleaned the system out. As Turbo suggested, spray all the linkages and roll the throttle stop to stop a few times, lube the cables and then see what you get.