CHILLGrandpa

I have to replace my cats and all i can afford are the ISR ones. Everything I have read said I will get a SES light and i heard mention of getting a tune.
Where would i go to get a tune and would that remedy the light. Will it damage anything running it without the fune.
Also i have a code P0420, it is defintely the car bank 1.
Will it hurt the car driving it until i can get it fixed?
I reckon another option for a while would be if anyone has a bank 1 oem car for sale that is still good.
I cant post in the classifieds yet.

AScobi64

If you're going to replace cats, it's recommended to do both at the same time. I also have read that there are some CEL issues with aftermarket HFCs. Although people seem to have good luck with Berk or Fast Intentions HFCs for a couple years anyways without issue. As far as I can tell getting a tune after installing HFCs is the way to go. Which you can find a local tuner through multiple different sources... Go on the tuner brands website such as UpRev or ECUTEK or Admin Tuning, usually they have an option to put your zip code in and it'll show you people around your area that install those tunes. Or you can do mail in tunes through Z1 Motorsports for example.

CHILLGrandpa

Thanks, all that said i just bought the car and apparently the previous owner had one cat replaced within the last year. I read the carfax and it showed that the cat was replaced. I kinda assumed that meant both for the reason you said.. So it has a fairly new oem cat on bank 2.

AScobi64

Yeah I mean if you know for sure that bank 2 was replaced, and fairly recently, I suppose it wouldn't be the end of the world to just replace bank 1. The trouble is going to be the different manufacturer per cat and possible different lifespan (before one throws a code) between the two having the mismatched pair.

Driving with a P0420 code is only going to damage the cat that has the problem more. Until eventually it affects other parts of the exhaust. You could get by for a little bit, but best to do something about sooner than later.

I don't know how much stock cats are, but if it was an OEM replacement on bank 2, you should try to match that on bank 1 or just replace both of them.

beefychicken

Not sure if they are still available, but this user listed a set of OEM cats last year. You could check on this, or search the classified section for other users selling OEM or HFC's. Most of the Cat listings are a bit old, but sometimes the parts are still avaialble for purchase.
https://www.myg37.com/forums/showthr...errerid=369648