Well from the sounds of all the symptoms you listed, id have to say... ... . PUT SOME FUEL IN IT!! Sounds to me like its outta fuel, but I assume you're smarter than that, so I'd think next either the FCA, or CP3 going bye bye.
If it was the CP3, would you expect it to be able to hold 27kpsi???? The FCA I could believe, since it controls the CP3... but if the CP3 will still hold 27kpsi?