My 2002 ssei has a p0420. i was told i need a new cat. has anyone run in to this problem
and can i run a high output cat or an empty cat? thanks

Sounds like your cat is not working right, or your rear O2 is not working right. If you go no cat you will get a a code. Was your cat changed recently?

I just got the car i dont know

Can't say for sure, but I believe that code comes up with a non standard Cat is used. There are others that would know more about that then me. That'* not a problem with my year. I seem to remember something about 00+ being funny about cats.

You can replace the cat, or cut it off and gain 5-10 WHP but then your car is not street legal and install a 02 simulator for $42 and never see the check engine light on again for cat issues!!



O2 Simulator, GM 4 Wire (1996-2003)

I just got this same code not a week ago! Looking into it more i found that the government requires GM to hold an 8 year 80K mile warranty on the entire pollution control system. Take it into the dealership if you HAVE NOT changed your pcm to intense'* pcm and have them replace it under warranty. Luckly i still had my old computer to swap in there before i took mine in. Also are you noticing that your boost gauge is running higher then it usually does? Mine was semi-restricted when i took it in. It would run at about 3 PSI of boost just to stay up at 65 MPH on the interstate.

how do i get that simulator?

If i tell you, then i have to charge you!! Just kidding... Here is the link on how to buy one... Rear O2 Emulator: 3800 Performance <---------------- Click here

I had the same code and it WAS the cat. I have 73k miles on my Bonne and The cat Was covered under Warrenty. As a matter of fact... The Dealership replaced the ENTIRE Exhaust from Cat to Tips because in 02 it'* a one piece system.) Cost me $0.00 If u had to purchase the same exhaust NEW from GM it'* almost $1,000.00

Good Luck

thanks!!