im a little afraid of it because it’s too cheap 😳….

 

I liked that it’s mandrel bent and 2” ID , not 1 3/4 , so it’ll let that 2.2 breath a bit better

 

If you aren't going to look for and fix the cause of failure it wouldn't be very smart to spend a lot of money on a part that will surely fail.
What brand O2 sensor was installed?
One thing that could be done is to have an old fashioned emissions gas test done to see if there is really a problem (the kind with a probe up the tail pipe).

 

I believe they were Bosch from Autozone…I guess when I pull the old one off I’ll see if there’s any damage. I’ve had the F/I cleaned all new plugs, new ignition box done already…coolant is new and the oil…code just randomly popped up..I’m going to change out the upper 02 sensor when I do the Cat.

 

If they're Bosch, try replacing them first, they have caused problems before.

 

Is it the original cat? If so, you would be throwing away a very expensive part, so be really really sure it’s necessary first. Sometime fixing other issues and/or taking a nice long drive can improve things by burning off some gunk in the cat.

How long was the P0420 set? (Time and miles. Wild guess is fine.) Do you take a lot of short trips?

Any other codes, now or before the the P0420? Any other issue before or concurrent to this one?

Which O2 sensor? (I don’t even know if there are two on this car.) And what maker and part number?

(Assuming not P04020 but P0420 Catalyst System Low Efficiency.)

 

There is a recall involving the programming TSB # 05-06-04-073 for the 2.2L giving false P0420. If the VIN is lower than 6S559494 it needs updated ECM firmware.
I was afraid you would say Bosch, they are a problem.
Here is a pdf of the TSB:
TSB05-0604-073.pdf

 

Yes , Bosch are a known problem, I installed GM


Up and down stream

 

That's not enough platinum to covert a single cylinder engine.

 

Is that tiny flex section going to do the job?