Mitsubishi Repair: 1991 eclipse gs, engine computer, switch circuit

Question
hi i rencetly replaced a a engine computer in my car and started my car but when i tried to shut it off it stayed running and the key was in the off postion so i replaced the ingnition switch and tried it again the same thing happened i have no clue wat to do i have no idea y the engine wont turn off it just keeps running normal

Answer
Eric,
For whatever reason, your ignition wires that connect to your ignition harness on your key tumbler switch are getting continuous power.  Sounds like there's a short somewhere in the ignition switch circuit.  This connection may be shorted when the car is first started at the new engine computer.  I'm not exactly sure remedy this other than tracing back the ignition line from the ignition switch and determine where the short is and why the it's continuously gets power.  You can put a kill switch in line with the ignition wires as a temp fix.
Good luck!