My speedo is bouncing around at 10-20 mph. I have a b16a swap with a ys1 transmission.

I'm not sure how the vss in these cars works. I have thus far been unable to locate the exact position of the sensor or speedo cable. I've found 3 connections on my transmission; the clutch cable, a sensor hookup towards the front of the transmission(aka radiator side), and something directly above the differential that looks as if theres 3 vacuum hose connections, only one of which is hooked up.

Any help would be greatly appreciated. This is my daily driver now, as my other car was sold recently.

 

The thing directly above the differential is the VSS (vehicle speed sensor) Sounds like a '90 - '93 Integra style setup. The hoses are for PS fluid, it's run through the VSS and the faster the vehicle goes the more the flow is restricted so the less assist you get from the power steering the faster you get. The Speedometer cable goes into the top.

 

Carefully remove the speedo assembly and check the gear for any wear. Also look inside the trans and check the speedo gear on the differential for any wear. You may also want to check your speedo cable as well. These things are getting up there in age and usually need replacement.