Yeah, you should just start by inspecting. You might find the sensors have a bunch of metal fillings on them. Clean the sensors, inspect the tone rings, and check the wiring from the sensors to be sure they are not cut.

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'84 190D 2.2 5MT (Red/Palomino) Current car. Love it!
'85 190D 2.2 Auto *Cali* (Blue/Blue) *sold*
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