[mgarblik]

Originally Posted by salem1912

Leave the gauge on,start it up and let it run the same as before. Shut off and see how quickly the gauge drops off and what your reading is after 1/2 hour. If it drops to 0 -10psi see how quickly it goes up to 50-55 (what ever the spec is) WITH just turning the key on. You could have either a injector leaking into the cylinders or a faulty pump check valve that's not holding the pressure forward.

To take the above to the next step. If it holds pressure, the fuel system has integrity. (regulator, injectors and fuel pump are good). If the pressure drops to near zero, you have an issue. You can use shutoff valves in the feed and return lines to isolate. Shut off return valve to the tank. If pressure still drops, leaking injector, (s) . Much more common issue is failing crank sensor. They fail in an intermittent mode all the time. Do a quick check for ignition, next time it won't start. Also, next time it won't start, hold the pedal WOT and see if it starts. That would indicate a leaking injector as well. 3800's are pretty easy to deal with for the most part. Take care.