Last week my recently acquired 91 245SE stranded my wife on the highway.
Symptoms (which the previous owner had related to me) were intermittent lurching, or as i would have said, engine cut off. Even that day we got the car restarted and drove it home.
I checked the IGN system codes- speed sensor malfunction.
I pulled the sensor and discovered the wires just as they entered the sensor body had lost most of the insulation and were either shorting to each other or the bare shield wire.
Cut the wires slid on some heat shrink, scavenged some mylar shielding off some old cabling I had and re installed. I think I'll add some of that split cable sheathing to protect the wires better.
Starts right up (haven't driven far though because next I checked out the lack of OD.
After checking all the wiring to the OD solenoid I pulled it off (best done by removing the transmission mount to gain access).
Checked continuity......open circuit.
Really didn't want to buy locally ($250 !)and resigned to ordering and waiting. I took off the cap and peeled away the rubbery potting compound. Found the magnet wire from the ground terminal into the solenoid body had broken at the terminal. Scraped back the varnishing on the magnet wire, added a small bare jumper wire and resoldered to the terminal. Now need to get some more potting compound. The solenoid now WORKS!

FYI= the auto OD solenoid has a resistance of 13 ohms and draws 1 amp of current.
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744-16v-4+OD 185kmi., 745-16v-4+OD 359kmi., 242Turbo-4+OD 170kmi?, 245DLT automatic 287kmi.. 245SE automatic 198Kmi.