5.3 Engine Question
If it comes down after a short time, I would suspect a bad injector. If so, I would then do the above test of removing the fuel rail to see if any are leaking badly or swap them around or out. Could try doing Seafoam treament the engine and gas.
Also check the Ohm reading of the ejectors coils, should be around 14ohm, could be a bad coil in the injector.
Good luck on finding the problem. Keep us posted....
BC






