You said the system is disabled. How did you come to that conclusion? Does the light in the cluster come on?

There are 3 sensors, the computer, the valve / pump unit, and some wires connecting them. By 85 I think the computer was smart enough to give you blink codes, I'd have to read the repair manual. Checking the sensors should be fairly easy, just unplug the connector from the computer and use a meter to check the resistance.

The whole system is very light. I'd guess that all of it together weighs under 15 lbs.

-J

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1991 350SDL. 230,000 miles (new motor @ 150,000). Blown head gasket

Tesla Model 3. 205,000 miles. Been to 48 states!
Past: A fleet of VW TDIs.... including a V10,a Dieselgate Passat, and 2 ECOdiesels.
2014 Cadillac ELR
2013 Fiat 500E.