Inconsistant starting

this is my dad’s van, maintained well w 56k. when it starts it runs well but may not restart if turned off mid trip, has had it to the dealer + other mechanic’s , found nothing, new fuel same problem. no codes.

Describe what happens when it won’t restart. Does it crank fine, but just won’t fire up?

If it cranks is there ever any smell of gasoline associated with the no start? The next time it won’t start mid-trip, floor the gas pedal while you turn the key and see what happens. If it fires up - and maybe runs roughly for a bit - then it may be that something is leaking fuel into the cylinders and flooding the engine. The first culprits would be a leaking fuel pressure regulator, or a faulty/leaking fuel injector.

do all the things cigroller recommends, if that is not the problem, 1. if it clicks but does not turn over, it is the starter solenoid. 2. wont click or crank it is most likely the starter or the starter relay. 3. if it cranks but wont start and does not smell of raw fuel, the problem could be in the distributor or vacume advance. 4. it could be a worn out ignition switch that is causing intermittent starting. 5. the coil could be defective, and failing when it is hot. 6 if your valves are warped it could be losing compression when hot and this could cause it not to start. try to post more symtoms so some of the other old geezers here can give you better advice than I can. Anyway you have a lot of choices to consider before you junk this thing.