94 XJS. 160k miles. Drive car & speedometer stays at 0 MPH on Sunday. Today fuel gage reads 1/2 full when starting car, car runs fine. Fuel gage reads zero during a short drive. Add 4 gallons of fuel to tank and gage still displays empty. Car is my fathers and is 90 miles from me. Before I visit him & tackle this, any ideas?

 

I would double check fuses & give it a full tank of gas. I know it is basic, but my fuel gauge/sending unit has started working with full travel and sitting corrodes these tanks badly.

 

Fixed! It was a loose pin connector on the back of the gauge cluster. Probably the bumpy freeways loosened it up...Free & easy fix. Cant beat that!