I looked through the DIY and didn't see this exact problem.

About once a week it will turn over and start but stumble along for just a few seconds at less than 500 RPM and die. It will not restart unless it sits for 10-15 minutes at which point it will fire right up like normal and run perfectly. If I try to restart it too soon, it will just crank and crank at normal speed and not fire and I will then have to wait an additional 15 minutes or so before trying again. It's like resetting that 15 minute clock each time.

The cel doesn't set and it doesn't throw any codes. It's never done it more than once a day and there has always been several days between episodes.

It hasn't happened if just running into a store - usually only if it's been sitting for more than an hour.

Our climate is hot and dry during the summer (100-115). It has done this during lower temperatures but is doing it more often now so I don't know if it's heat related or if the fault causing the condition is just getting worse.

Any ideas where to begin looking for the trouble?

Thanks.