redantporsche

I have a 1983 928s. My speedo and odometer were working and they both stopped functioning (~54,000 miles). All the other gauges are working so could it be just the odometer gear? What is the best way to proceed to figure out the problem?

Thanks for all your help in advance.

Jerry Feather

Go onto the 928 International site by Google, and find their section on tips. Find the one on how to replace the gear on the speedo. It is really a great site. I have used the site to change the odo gear on one of my spare instrument clusters so I can replace it in my 82 which has the odo and speedo also malfunctioning. I'm not sure what the issue is with the speedo but the odo gear was failed.

There is also a recent thread here with that site linked.

Mrmerlin

if the speedo and the ODO are not working then its probably a wiring issue .
I would begin with an inspection of the sensor at the back of the transmission,
then follow the wires into the spare tire well look for cut wires.
What was the last thing you fixed?

redantporsche

The first thing I did when I noticed the non-functioning speedo was to look at the wires under the cover in the spare tire well, and those looked ok, but I'll do a closer inspection.

The last few things I worked on was in this order:

Fuel Lines
Gear Oil change
Coolant
Bulbs in Tailights
Reostat Dimmer

Mrmerlin

Of those the oil change in the diff could have jostled the sensor wires
Then the pod connector since you were working the rheostat

you could have moved one of the gauge connector s

Jerry bumped a thread on odo gear repair but it also shows the pins that run the speedometer these could need some deoxit

so might want to check the ground bundle behind the Rr interior hatch liner
remove the lower hatch floor tie down then use a 2x4 to hold the liner back so you put your hand in and loosen the bolt then spray with deoxit 100 then tighten the bolt