It is a 6 cylinder and this only (I thought) occurred during the winter,
until yesterday. I like the idea of a vapor lock since the fuel does
contain ethanol (see Tester’s comment). Also, that would be an easy thing
to check. The shop had checked for sticking throttle, etc. but found
nothing. I am a good customer of theirs and they did not charge for any of
their checking but couldn’t find anything.
I remember, as a kid, my dad driving through the mountains of southern New
Mexico and using half a grapefruit for the same reason. It was a 41
Studebaker, flat head, with four doors that opened to the center. There
was a clear view of the pavement around the clutch and break peddles.
Do you know if the gas recirculates to keep the line cool? An old Buick
did that and had the same problem (but worse) caused by some metal filings
in the fuel injector restricting the return flow allowing it to overheat.
Thanks for your suggestions as well as a thanks to Tester.