About a month ago when my car was missing under WOT on the hwy i had the CAT replaced with a high flow one, it was awesome on the hwy no miss at all.
Now tonight im on the hwy its -22 F i floored it, it went to 4000 then hopped around at 3000, also when i let go of the gas, i can feel a slight griding and i can hear a small whine when i feel the grind, this is around 40 mph + accelerating...
What else is wrong with this car!!!!

Matt, disconnect the battery for 30 minutes. Re-connect it, and go out and duplicate the problem for a couple days. Then pull codes.

It'* POSSIBLE that the clogged cat contributed to plug fouling, but lets make sure.

okay ill do that first thing tomorrow!
Thanks

Also a thought. Could your O2 sensor have contributed to your plugged cat?

Yes, it could. If it was bad for long enough.

i did a code scan, it came back with code 22...TPS voltage low.
Im assuming then i need a new TPS, kinda makes sense because i can hear/feel a whine in the accelerator.

Make sure........check for TPS voltages. If you don't have a book, it'* posted here somewhere. That won't cause a miss, but could cause you to run lean or rich. I'd be curious to see what your plugs look like. I know it'* a PITA, but you might consider pulling them. They can tell a story.

well to better discribe it, its not like a mis, its like the car is serching for the correct rpm at WOT,

okay so i tested it with my multi tester,The book says with the IGN on, the TPS should read 0.5 volts, mine reads 0.9, it then says to slow open the throttle until WOT,
At WOT it shoudl read 5.0 volts, mine reads 3.9 VOLTS...
So this is what im assuming is the problem here.

The TPS can affect cruise control, too. Depending on the type of TPS failure.