this could be a lot of things, whether from sitting, being broken down, or put together..

why does it run for two minutes? is there a cel?

injectors pulse with fuel pressure, if it idles for "about" 2 minutes, its probably running off the pressure from the fuel pump priming, and then runs out of pressure as the fuel pump does not continue to run. this could be oil pressure (since the engine sat), the relay, or some other sensor.

if he can check to see if pressure is lost in the rail, that would verify it, most other cause for pulse issues (sensors, spark signal, etc) would through a code.