'97 intermittent backfiring and power loss at 4k+

started doing it a couple days ago and I figured it was teh cat, so today I finally crawled under it and gave the cat a few whacks but its not rattling... could it be something else, fuel pump maybe? it idles fine and runs like a champ up to about 3700 rpm, and sometimes it'll run perfect throughout the rpm range, but it seems like the more I drive it the worse it is getting, and there's still no CEL. I just wanted to get some oppinions before I start throwing money at it

97 xj, 4.0, aw4, 106,000mi, all stock except k&n (~2k since cleaned/oiled), APN header (checked and no leaks on exaust or intake), accel coil (~15k miles) it does have ~10k on the cap/rotor/wires/plugs so it is due for a tuneup, but I checked the cap/rotor and they still look 100x better than when I bought the jeep and it had 75k on the original cap/rotor, plugs look fine too

anyone?
I guess I'll pull the cat off today and see what happens, the lack of CEL is leading me to believe its not related to fuel or spark.

if the cat checks out okay could something have collapsed in the stock muffler creating extra backpreasure? I suppose I'm getting a little ahead of myself here, I'll post back with my findings on teh cat

ok, pulled the cat (what a PITA, thought it'd be easy with it just being clamped :wierd cat is fine, not broken up, can see light through it etc
took it for a drive with the cat and muff unhooked and it still has the same problem

I guess my next step is to buy a fuel pressure gauge before throwing 2 bills at a new pump, maybe I'll get the cap/rotor/plugs just to rule that out too

And maybe check your coil.:wave1:

kinda weird, I checked pretty much every sensor, did a full tune up, chased around a bunch of other ideas and checking stuff and no change... then I had a few CELs from running around with various sensors disconnected so I disco'd the battery to reset the ECU and its been back to normal for over a week now, no backfiring, no power loss, runnin like a raped ape again :dunno: