Sounds like out of the millions of valves, you happen to have gotten one bad one

 

Well I guess, nobody I've talked to has heard of this or being common, maybe it was just a bad valve, I'll keep looking into for awhile and maybe something will come up or maybe not. Thanks to all responding!
Greg

 

By the way, the way OBD-II is supposed to work, when the system detects multiple misfires in any one cylinder, it shuts off the injector for that cylinder. If the cylinder starts to fire again, and it somehow happens to get fuel from another injector, (not really possible, but who knows, maybe the injector is seeping), you could wind up with a REALLY lean mix in that cylinder.

In other words, with all the misfires you were getting, the system might have been shutting off the injector on purpose.

It's a stretch, but... hey...

 

tuliped valve on babied 98 4.6 expedition. #8 cly. no good explanation other than the headgaskets were bad. puttin it back together now... from my phone.

 

Does that engine have PI heads? Didn't the early PI heads have an issue on the #8 valve, or was it #4? something about cooling? Usually it would start ticking first...

 

they are not PI heads. i do think it was heat related. i wish i had they guy at the machine shop mic the rest of the valves. the lifters also were not bleeding off good but he said i shouldnt have any trouble with that. i originally pulled thehead for a leaking head gasket on pass side and no comression on #8. thought it was a miss first. the knock sensor wires were broke off next to the sensorunder the intake too. that might of changed the timing but no code other than multiple missfire

 

I got it back together and it still had a miss. Flashed the missfire on 7 and 8 in two miles. Looked around and found the plug wires on the drivers side coil were not what chilton said and corrected it. Runs great now. My friend that sold me that expedition must have got them mixed up some time back and I think that might of made that valve tulip.