This could be a couple different issues and it depends on how it actually shuts off. Does it just suddenly stop like someone shut the key off? If so this is most likely the idle air control valve.
Here is a guide on how to service the IAC in general terms. Your IAC is a little different and the process is attached on how to remove it.
The next most common cause would be a fuel pump issue but this would be if the vehicle sputters a little and then shuts off.
I attached the fuel pressure spec which we will need when monitoring the fuel pressure. I would just hook up the gauge and start the vehicle and monitor the pressure. It should remain steady even after the engine is off. If it is dropping then it cuts off, the pump is the issue.
Let me know if there are questions and we can go from there. Thanks
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Monday, March 30th, 2020 AT 7:36 PM