Look for a differential speed sensor or wire.

The connection is under your rear seat base.

You may be able to remove the sensor from the differential, clean it, re install, and have this issue go away.



Have a great day.

__________________
ASE Master Mechanic

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Thermal & Aerodynamic System Engineering (TASE) Senior vehicle instrumentation technician.
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1985 300SD
1983 300D

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