Another Speedometer Question

[snowyred180]

I just bought a 1991 Nissan 240sx hatch with an SR20DET swap. I'm loving it, but the speedometer doesn't work about 90% of the time. When it does work, it's shakey at best (arthritus needle thing going on...) Some of the time it reads like 90 when I am going 50 mph, and sometimes it reads 130 mph. Most of the time it just reads 0 though.

I've searched, and searched, and searched so much that my head is about to spin (and I'm not even drunk).

I checked and found the two yellow/blk wires going to the transmission, and the plug appears to be fine. Any suggestions? I'm thinking the speed sensor went bad, but I wanted to see if anyone else had this problem before I went tearing stuff apart or take the car in to get it fixed.

[snowyred180]

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