Fox Help I think my speedometer broke

[93CalypsoConvert]

Hi all. I was driving today and all the sudden my speedo needle shot up and bounced off of the trip reset arm. Then it went back to functioning, however it is reading high now.
It still goes back to zero when I stop. I can hear clicking coming from the cable behind the dash now too.

The faster I go the more correct it gets.
It says I'm going:
15 while barely rolling
25 while doing 10
35 while doing 20
40 while doing 30
45 while doing 40


It was spot on before.

 

[General karthief]

Cable frayed possible

 

[Mustang5L5]

I bet the little tension spring got overstretched when it pegged. Unfortunately can’t repair it as that’s part of the calibration process. Will need a new speedo or find an old school speedo repair shop.

It will most likely be cheaper/faster to buy another speedo, adjust the mileage and swap it in.

 

[Boostedpimp]

Yup either the cable, tension spring or the plastic gear in the side of the trans is missing some teeth now