having high rpm performance problems in a stock 02 galant 2.4L

[djknox27]

Repalced flex p ipe and got a temp test done on the cats..weird stuff like unplugging the o2 sensor dosent seem to make a difference and MAF sensor unplugged car still runs
fine can anyone give me some insight on possibly sensors or any suggestions?

[Voodoo]

Moved to 8G Car Problems

[charris]

When you unplug the MAF sensor, does it run worse? I think it's normal for the car to run, it just runs horribly.

Can you describe the "high RPM performance problems?" Does it lose power at high RPMs?
Does the engine occasionally die as you come to a stop/idle?

If there's a fuel/air problem (like from a vacuum leak), it will run the fuel system in open loop AKA not use the O2 sensor but just dump gas into the fuel/air mixture. So removing the O2 sensor wouldn't make a difference.

Is the check engine light (CEL) on? If so, what codes is it throwing?