Just throuhg experience, I once had an old Alfa, which I was mollycoddling along to get to a fuel stop. I reckoned it was about due to come to a halt, when lo, it did.
I walked a couple of miles to the station, filled a can, and walked back. When I tried to start, the car wouldn’t fire.
I called the AA. They agreed it sounded fuel related, but after over an hour, cound’t get it going. He rang HO, and after a tecnical discussion, (they have a database of breakdowns) one Alfa like mine, had broken down once before, with a failed balance resistor in the fuel injection – nothing to do with the fuel situation. The guy “shorted” it out or whatever, to get me going, and hey presto…
So the 4m walk was entirely wasted….
Don’t always assume the source of a breakdown is obvious.