1996 F150 4.9 5 spd - 200k Ran pretty good then.
Initial symptoms were that the truck ran good for 30 minutes, then lost ability to maintain smooth idle or pull rpms. Last time it died, on the way to the second shop, I noticed the pipe prior to the cat was red hot. Spark plugs, gas wet and carbonized after any start via sparying gas in intake.
New cat because the old looked plugged after disecting it. Fuel pressure after three cranks pushed 50-55lbs, when running around 60. Fuel pressure would bleed down after around hour. Checked for spark, bluish. Computer checks out as does ignition module. Dist cap, rotor, plugs, MAP, EGR Sensor, checked or replaced. Visual inspection on and off rail seem to indicate that fuel pressure regulator is functional. Will run off of gas sprayed in intake. Both fuel pumps run normal. Fuel filter first thing replaced, very, very dirty but at least front tank doesn't reflect any sediment whatsoever.
Absolutely any clue or direction appreciated. So far worse case of fixing everything but problem I have every experienced.