Hi all,

In a nutshell, I was driving down the highway tonight and got a check engine code. Scanned it when I got home and it's throwing P0420 Catalyst System Efficiency Below Threshold (bank 1) @ me.

No prob, I did my research and understand that this is a Ctalyst converter error. My question is this: Since my cat is only 3 months old do you think that it is really the cat that is failing.

Important: This new cat is a vibrant race cat (I assume this does matter) I'm runing it with AEM V2 intake, Type R oem replica header, and skunk2 maxpower exhaust. I salvaged my O2 sensor when I installed the headers as well. Since that o2 sensor is orignal (and I did have trouble removing it in the 1st place) could it be starting to fail and as such be sending incorrect data to the ECU which would trigger the wrong ECU code?

Let me know what you all think.

Thanks!

 

Bump...

Is this a common thing with aftermarket "high flow" cats?

 

I had a lot of problems with my magnaflow cat on my old car and was constantly throwing that code. I was also having problems with my egr system so I don't know if one problem caused the other. My cat ended up imploding and being replaced under warranty but I still ended up throwing the code later. I have a Random Technologies cat on my new car (same as yours 99 Si) and I am also throwing that code. So in my experience yes aftermarket high flow cats can contribute to these codes, but more than likely there are other factors contributing to it.

 

Thanks for the info.

I would think it's still safe to drive without worries or damaging anything else?

Of course, that is assuming it is not clogged or something.
I had some flanges welded on there so I could bolt it in / bolt back in the stock cat for emissions testing. I'll check it to make sure it's clean inside. If it is, I should be safe right?

I just want to make sure this can't lead to other issues.

Thanks for your help!

 

Check my sig for link - you will be very happy =P

 

Do the sparkplug non-fouler cheat mod.
http://www.energeticforum.com/renewa...n-foulers.html

 

Thanks guys!

EJ8 - the link in your sig is broken: The page you're looking for doesn't exist. You may have selected an outdated page or mistyped the Web page address (URL). Sorry for the inconvenience. You would be redirected to the homepage now ...

Must be the upgraded forum-ware.