Wanted to log this odd experience on the forum...My 99 with 440k sat for a little over a week. Turned over, started and stalled right away. After sitting for that long, it usually rattles a bit upon starting until the oil pressure catches up. I run Castrol High Mileage with some Lucas. I use about 1/4th of a quart of oil per 5,000 miles. There is less than than a year on the fuel pump and filter. Original Starter, original Crank position sensor. Ambient temperature 78 degrees F.
Tried starting it a second time and the starter started sounded strange, like the ring gear was slipping a little or there was oil where it didn't belong slowing the starter speed down. Not like low voltage slow, it sounded like the starter motor was working normally but something on the mechanical side was either slipping or slowing down the revolutions of the engine.
Put a jump box on the battery, no change. Same weird starter sound. Tapped on the intake manifold a bit in hopes of rattling the starter back into it's normal speed. Cranked again, No changes.
Had the wife crank on it while I was under the hood and it appeared to be cranking normally. The mechanical fan was turning, but still no fire. I swapped EFI fuse, which I was thrilled to find was wearing out (this would be my 3rd in 14 years) thinking that I would be saved by a simple fix yet again, but still no fire.
Checked for CEL codes, found none. Disconnected/reconnected the battery, tried again, no fire.
Had her crank while I was tapping on the intake manifold and it finally fired up with a thick white cloud of smoke out the tail pipe that quickly went away. Been starting and running normally all this week. No smoke.
I'm not sure what the issue was, but I stumbled across this thread and thought it could be valve seals. It was the hardest start to date. I'll report back if/when it happens again.