Engine keeps shutting off?

hi what would cause a 1999 porsche boxster with a 911 motor and trany when i push the start button it starts right away but shuts off within 6 seconds or if i press the gas sometimes sooner saying that some times it works great for weeks scared to drive too far incase it leaves me stranded it just shuts down for no reason i had this looked at by man certified mechanics and even the porsche dealer couldnt fix the problem all the electrical has been replaced and the computers also have been replaced any advice would be greatly appricated thanks

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This post was auto-generated based upon a question asked on our tech article page here: Pelican Technical Article: 911 Fuel Pump Replacement

[Wayne 962]

I'm not sure - if the dealer could not diagnose the problem with the factory tool, then it must be some type of intermittent problem that may not show up during testing. I will copy this question to our Boxster forum, and perhaps someone there has some additional input.

- Wayne