12volt feed back on ignition outputs

[rayhall]

I am still trying to find why my DBW foot pedal and throttle body signals are been offset. At first it was the 12volt AC request going to a volt input doing this. But the problem is still there but not as bad. So I am trying to find why.
I have two solenoid valves driven by spare ignition outputs. These feed 12 volts back to the ECU pin with the ignition on. Could these be upsetting the 5 volt supply and causing the offset signals for the DBW.

Ray.