Weired electrical problem with the tach and speedo

[njdaewoo]

I have a problem with my car and its a problem I've never seen. When I start my car I have noticed that when I rev the motor the speedo moves even though I'm standing still in neutral.If the car is idling, the speedo stays on zero. I bought this car a while ago and I noticed some butchery to the ecm wiring below the dash. It looks like the previous owner might have had a Apexi controller installed at one time. After selling the Apexi controller he looks like he just tied the wires together an put black tape on everything. I have checked the wiring and it looks like everything is where it should be.