Firstly, thanks, master486, for the reply!
I've not yet done the MAF yet... I'll likely get to it tonight.
Resetting the computer... I seem to remember a help page 'round these parts... I'll do so. Gotta find it though...
The car does have 136.5+K on it. I *guess* I could replace those Oxys... if nothing else works I will.
The cats were plugged a total of 1 entire day. And I babied it home that night it happened. Of course, if they were plugged before then, I wouldn't know about it. It just sorta... *happened*. Car had never had a problem with power before until then.. and it all of a sudden, within about 10 minutes, it started this gradual power loss, then it (apparently) blew off one of the DPFI sensor hoses... and it ran like crap.
That hose was fun to figure out, BTW, never having to deal with it before... After I learned what a P1402 was... it was easily fixed with a new hose. Amazing how loud that little bitty pipe can be..
Anyway, it sorta just all of a sudden did that... I got it home after about 40 minutes... It was strange... I had rememberences of my sister in law crunching hers on a parking stop she ran over (didn't know it was there and took off. Nice.) That was how it acted (88 cougar v6, btw) and that was how I immediately knew what it was.
Took it to an exhaust shop the very next morning and got that taken care of. So.. running time... maybe 2 hours, and as babied as I could.
(long story short.)
Currently, the car otherwise seems fine. Doesn't hurt the power any when it's not missing. It's only that "twilight time"... and it goes away, I can get it to stop it within 5 minutes now.
The CEL blinks sometimes... you know the computer's not happy when it blinks...
But after restarting it stays steady on... due to the P306.
I think it's the injector. I'll be replacing it/them (depending on how much is left in my pocketbook after all the adventures this car has put me into this month... Sigh) tonight. Gotta lift that dang plenum again... ugh.
The "going away" part has me thinking that's it... if it's leaking a little until the pressure's gone from fuel rails... that cylinder has a little liquid gas in it, right? Which means it either it has to evaporate (over the course of a couple of hours, not a problem, eh?) or it has to get gone somehow... Which is why it goes away if I get the engine warmed up a little... and then stop it... the heat causes it to evaporate quicker... and the car runs right!
Right? Or am I just drinking the wrong coffee?
Thanks again for the advice! I will let you know.