Do you have spark when restarting after 5--20 minutes?
Do you have fuel pressure when restarting after 5--20 minutes?
Does the scan tool show RPM when cranking during re-start?
Good questions, this always seems to happen when I'm far away from the garage, to check these questions when on the road with a hot heat soaked engine.... Let it cool off for 10 minutes and it starts and runs just fine, can idle in traffic hot with no issues. Randomly rears its head when trying to restart when over 90 outside and engine is hot from long drive or long idle time after long drive.
1. Spark i would have to either pull a plug or get one of those lights that go in a sparkplug wire. - If no spark then its the crankshaft position sensor or something in distributer?
2. Fuel pressure would be easy check by checking for fuel spray from the Schrader valve on fuel rail? If no fuel then its the fuel pump, fuel pump relay or regulator?
3. I have one of those cheap code readers that connects to my phone. watch the rpm live data while cranking, if none then its the crankshaft position sensor?