Past couple days, my '03 3rd Gen began cutting out/stuttering and blowing white/gray smoke whenever I get on the pedal relatively aggressively, however, if I go easy and baby the pedal, I can keep the cut-out/stutter from happening. Aside from that, truck starts right up, idles fine, avgs 17 mpg around town and the check engine light remains OFF. Only thing I've found that's out of sorts... the truck's lift pump pressure (via my Quadzilla XZT) is reading in the 50s vs the normal 10-12 psi, which I originally figured was nothing more than a glitchy Quadzilla XZT lift-pump pressure gauge sensor, but now thinking the excessive lift-pump pressure is a sign something more serious is going on, like a "bad/open" injector might be back-feeding pressure out to the rail(?) I've actually stopped driving the truck to avoid causing some kind of expensive catastrophic damage to the valves, cylinders, or piston heads + the cut-out/stutter doesn't instill much confidence should I need to get on the throttle to avoid an accident. Any help is appreciated, thanks!

 

Is it possible you just picked up a bad batch of fuel? Drain some fuel from the bottom of the fuel filter housing into a cup using the drain valve. Check that for water or other contaminates. Change fuel filter and take it for a short drive to see if the stuttering went away.
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