speedometer issue

[jim928s2014]

please can someone answer and help

i have a 1984 porsce 928s automatic
has a speedometer that drags intermediately
cluster was reworked, speedometer sender was replaced
still is dragging
once car warms up it works and then all of a sudden it will not work accurately it will drage and not record the speed

what has to be fixed/replaced?????

[hbueno]

Is it possible there's an intermittent connection somewhere between the sender at the transmission and the cluster?

Hguo

[The Deputy]

Do you notice any issues with the odometer? Or is it just the speedo?

If it is both, I'd go to the trans and look at connections and wiring. If it is one but not the other, I'd look into the speedo head/dash assembly. A very common issue is for the odometer to quit working on these cars. We had someone here that had an issue like yours resently, but I don't know if he ever posted the repair made.


Good luck,

Brian.

[JK McDonald]

Hey Jim - The speedometer magnetic pick-up signal starts at the back side of the differential and then heads toward the front of the car. You should 1st check the wiring connector located in the spare tire area. With the compact spare tire removed you will find a (sometimes troublesome) spade connection up near the far end of the recess as you lean in from the rear hatch. If you're lucky this will fix the problem.

A while back I had a speedometer signal that would become erratic once things warmed up after an hour or so of driving on interstate. It turned out that my intermittent problem was a poor contact on the edge connector as the signal entered the instrument panel. I finally had to pull the instrument pod / instrument panel circuit board and clean the edge contacts with a soft pencil eraser. A bit of a pain to get at - but this did cure my problem.

Good Luck, Michael