2004 F115 Starting Issue

[fishnwindsurf]

I have two 2004 F115 engines. Both run well but one starts on the first crank and the other has to turn over 2-3 seconds before it starts. It has always done this.

Is there a check valve that retains the fuel pressure so the engine starts up quickly? Could this be the problem with the hard starting engine? I assume it has to turn over a couple of seconds to build injector pressure.

Thanks