Quote Originally Posted by Ehwick View Post
...The engine doesn't sputter and then stop. It just shuts off like you used the ignition key ...
When I pulled the fuel pump relay in doing a baseline compression test on my '05 a few years ago, I don't recall any sputtering or struggling to stay running. Not saying it's fuel-related, just that it's one really easy diagnostic test which should be able to either rule out, or confirm fuel as the issue.

...could it be a engine temp sensor that is going wacky?...
You have an unusual set of symptoms, and IMO nothing should be ruled out until testing proves it to be ok. If carb cleaner doesn't keep it running, next I'd try gently moving all of wiring around a bit, right after the cold start up. Doing that could potentially flush out a bad connector or wire, if the pattern of the stall is changed by doing that.