Hi chio38,
You're right. It is a weird craving. Everyone is different. Personally, I can't
stand the smell of gasoline and I can't wait till I fill up my car, pay for the
gas so I'm able to leave. When my husband is with me, he always volunteers
to fill my car with gas. Anyway, you might want to tell your family doctor
about this weird craving. There might be something in the gasoline that
your body is used to. I don't know what that might be, but your family doctor
might and your family doctor might also give you some advice and suggestions about what might be causing your heartburn and stomach cramps. Good luck finding out what is going on.
What you are describing sounds like PICA please see a doctor.