AHHH HELL i've run out of ideas!

OK! so i went to the junkyard, got an instrument cluster AND a speed sensor; put them into the car, in every combination possible! (new sensor old cluster, new sensor new cluster, old sensor new cluster)......

I STILL CANNOT GET MY MPH GAUGE AND ODOMETER TO WORK:banghead: Check engine light is still on for VSS code and knock sensor code.... Help me, PLEASE! I have NO idea what to check for if i tried replacing the only possible culprits of the problem! It's so enraging to have a great functioning car that i cannot tell how fast i'm going in!

Help............

PCM? or wiring. try tracing the wires for the vss and see if there are any breaks in the wires