Thats kinda what I was thinking. Spark issues usually show face under a heavier load, it sounds to me like a bad coil pack or multiple cylinders, or even a weak alternator/battery causing a weak spark.
The "bad gas" theory isn't going to "stick around". Once its gone, it usually doesn't effect anything after you burn it off. If it was the fuel filter, it would stay clogged, not just be effected under WOT conditions.
I'd suggest doing to the easy stuff first.....take it to AutoZone and have the codes read, and also have them check the charging system.
On the other hand, maybe a better description of the problem could help us more.
Does the car shake or does it feel like its hitting a rev limiter and won't go any higher? If the IMRC's are stuck shut, the engine will go above 3k under light load, but if its trying to get more air under WOT conditions, the engine will starve because the IMRC's are shut.
Try this.....put it in first gear and try to get the RPMs above 3k under normal acceleration, but don't shift the trans. The RPMs should still climb all the way up to redline, but if you try to give it a lot of gas it will bog down. Try this and let us know......remember, granny it in first, I bet you can get past 3k.