My dad has a standard 10/89 EA Spack Sedan 3.9CFI 3sp Auto, the auto was replaced recently and I think the speedo is off now. I think that the speedo sender might be wrong, not sure. What should I look for if i get underneath the car?

a thing screwed to the back of the box with a thick wire attached to it,,not the one on the side.

just undo the single bolt and replace the transducer,it just pulls out and pushes back in,good luck

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