My 1988 Jaguar Vanderplus shuts down while driving down the road. It does not matter how fast I am going either. Please help.

 

hopefully some one will shift your post to the correct forum , for the best help and understanding of your car ,
I'm going to say most likely a failing fuel pump , but that is a wild guess with no data or tests provided . there are two many possibilities to pin point this with just guessing a possible dying component or posable wiring/earthing issue .
sounds like you need to rule out fuel pressure first and try to replicate the issue whilst monitoring the pressure then if need be check relays earth points filters and ignition and so on . best of luck.

 

Can DIY your repairs?

If not I would get rid of the car.
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