97 Civic DX Auto Trans guage problems.?

Ok, the speedometer had messed up so I changed the transmission fluid, Along with a new VSS. Well it fixed it some what... The speedo only jumped when decellerating. I noticed when I cut on the turning signals the needle goes crazy compared to what it normally did. Also the faster I go, the more the speedo variates. Normally 5-10mph difference from actuall speed. Before I put the new VSS on the VSS code OBD gave me said VSS malfunction/broken now with the new one it says VSS A Range/Performance. Others on Y! Answers suggested taking it off and re-tightening it. I did, No difference.

So really what my question is, Could this be wiring problems? The car has over heated before, But it ran fine after words, Gave it a Timing belt kit and water pump kit. Car ran fine. Or could this be some "Remanufactured/New" part problem. . . The car does had JDM header and SRI performance head(milled/port n polish), plugs, wires, distributor. Could the VSS have read A range/performance since I started building it and it just trashed out along the way, and this one is doing the same? For some reason of the Aftermarket parts? No clue where to begin if its not VSS...