My 69 mustang is odd. There are times where I drive it and it runs normal. And there are times where I’ll drive it for over 30 minutes or so, park it at a store for a quick 4 minutes, come back only to crank my mustang but it won’t start. It has gas and I floor the gas pedal while I crank it but to no avail. The more I crank it or longer I done it the more it’ll crank slower and slower which I don’t like. Has this ever happened to anyone? The only solution that works for me is to wait for about an hour or so and eventually it’ll start, which is odd.