Hi, not sure where else to put this but I need some help... I have a 2008 G37s coupe with an ARK Grip dual exhaust. I'm failing inspection due to a Catalyst error cause of my catalytic converter. Any fixes or anything to make that error go away? Please help! Thank you.
-Kory

 

Gonna need more information than that. Is it failing due to CEL light? Or going over on the sniffer test or failing visual inspection right off the bat?

 

It's saying Monitor Catalyst when they plug in the sensor to my car at the end. It's from the emissions test

 

Just to clarify, they're putting a sensor in your tailpipe and not plugging into the OBD portal underneath your dash/steering wheel, correct? And the only exhaust mod is the Ark? The original catalytic converters are still on the car? Unfortunately you're well outside emissions warranty even in California. You may have to fork out for some replacement parts.

 

No it's going in the OBD and the entire exhaust system is ARK, with Stilen headers. The cats aren't stock

 

That's probably why you're failing. If you don't have stock cats you will fail emissions inspection. Is your CEL on?

 

It is but the previous owner says it happens every 6 months, when I reset the computer it stays off

 

I don't know what aftermarket cats you have but you may consider looking into 02 bung extensions for the rear sensors if there's room for them. And you'll have to reset the computer and go through a complete drive cycle too so the computer can run through all the checks. Do you have an OBDII reader and smart phone app so you can look to see if there are any codes right before you go get tested?

 

I have a guy that will check for me, but the O2 sensors seem like that's ok but I was told I might have to put the stock cats in the car

 

Maybe...but if you're only periodically throwing codes, and they're just using the OBD port, it's a matter of properly clearing the codes in the ECU and then having the ECU run a full "check". If you just clear the codes and drive the car in for testing, it'll throw a flag in some states. Moving the rear 02 sensors back out of the exhaust path further may prevent codes from popping back up.

You can get a little bluetooth dongle for your OBDII port off of Amazon or Ebay. They're like $30-$50 for a decent one and I'm assuming you have a smartphone. Most of the apps, that read codes in real time, are pretty cheap, even free.