Many times on early cars the wiring at the tank sensor crack & you can get that dancing.
Just remember that this is only a variable resistor & over time they ALL will wear out.
The newer cars ie; 1995 & later DID have a design problem and they say it is due to the LOW EMISSION gasoline that is used here in the US.
MERCEDES Benz Master Guild Technician (6 TIMES)
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190E 2.3 16V ITS SCCA race car (sold)
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