[1989toyotasupraandpickup]

So here is the story. i own a 1989 toyota supra turbo. the problem i am having is the voltage at idl and e2 at the ecu. When i probe these leads i get 10 volts instead of the 4-6 that toyota calls for. when i unplug the ect for the transmission the voltage across idl and e2 drops to 5.2v. this is where it is supposed to be. Anyone know what the problem may be.????? please someone help i am ripping my hair out wondering where the problem may lay. thanks