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Hello, my name is Joe
I will assume your coach has either a Cummins ISB or an ISL engine.
If you can hear the electric fuel pump rumnning when the ignition key is cycled on, then that tells me the engine hasa good power and ground feed to the ECM (COMPUTER) and "should" start.
From your description, the most likely cause of the engine shutting down is that there is air in the fuel lines between thefuel tank and the engine.There may be a very small leak that allows air to enter the lines or one of the fuel filters as fuel either drips out ordrains back into the tank. This type of "air lock" will usually cause the engine to run for a short time - until the fuelin the line at the engine is used up. The engine stalls when the air reaches the injector pump.
You can Try removing the the fuel filters and filling them with fuel and repeatedly cycling the key and electric fuel pump attempting to restart.
Sometimes the primary fuel filter will have some type of manual fuel primer pump also.
Just checking in to see if you need any clarification on something which I stated above. Please remember to rate my service, so I can receive credit for my help. -Joe