You will get a code if there isn't a catalyst element between the front O2 sensor and the rear O2 sensor. It doesn't matter what shape that pipe is. Midpipe, test pipe, race pipe, etc are all varying terms for the same thing. They may or may not have a catalyst element in them, you will have to read the descriptions. The OEM cat doesn't really get called anything different, because it is rather expensive so no one in their right mind guts a working cat. If a dead one is gutted, it is just referred to as a gutted cat.

 

Yes, PO420, cat below threshold.
I have the BHR Pipe. Mine pops up every few days, takes a minute to clear it. Torque app is a good analytic tool, also gives you your real coolant temps since the factory gauge is almost useless, & overheating is a leading cause of engine failure.
The de-foulers don't work so don't waste your time.

 

Mine is gutted and i get CEL once every 8000 miles or so....usually if I'm in stop and go traffic. i went advance and bought a code reader that has the ability to erase codes.. it works for me. I've passed NC emissions inspection twice with a gutted cat...

 

and if it hasn't been mentioned, the materials in the stock cat are worth upwards of $300 to a precious metals/cat recycler.

gutting a working cat(or even a clogged up one) is just dumb, you could sell it and buy a test pipe and still have money left over. there's a reason they are so expensive and it isn't just because it is an OEM piece, half of the cost goes into those materials.

 

That's interesting. Mine started out with long intervals but got more regular as time went on. I wonder why.

 

I'm not sure....it could be that i have a 2 1/4 inch piece of pipe shoved through it. the only time i get a cel is when I'm in stop and go traffic for a long time. Running highway speeds or playing on back roads i don't seem to have a problem.

 

if you have a pipe shoved through it then the downstream O2 sensor is obscured, not reading the rich mixtures.

 

Yes even with a mid pipe you will eventually throw a code. The accessport can be coded to basically "cover" that code up. Some members have gone as much as 2 years i believe without a cat and No accessport and No code. Many and Most like me though as soon as you gut the cat the CEL light is on.

 

just ignore my last post. lol

 

My 2007 Mazda RX8 after I gutted my cat with Greddy Elite Catback exhaust:
Posted From RX8Club.com Android App

 

Gutted the cat last week, drove the car today and no engine codes at all! Does this mean I should pass emmissions or will it still fail?

 

I think you will pass emissions as long as the code does not show up, im sure they will wonder why they are choking on the horrible fumes the rx8 makes without a cat though..

Also almost all rx8's will have no codes for a day or two after hollowing out the cat but you will more then likely have a P0420 code soon, if it happens and you want to go for a e-test just clear the codes before going it should give you at least a couple hours of driving before the code comes back.

And one more thing is to make sure you don't just unplug you battery to remove the codes because you will also lose your short and long term fuel trims which will make you fail the e-test unless you drive a good 50 miles to relearn the fuel trims before going.

 

Just passed my NC state inspection again yesterday with a pipe thru the cat.....it was a Good Day

Posted From RX8Club.com Android App

 

I'm kinda Broke... So I think I'm going to have to do this. I'm terrified of getting under my car and doing this but savings aspect is a big deal.

 

Why do you want to hollow out your OEM Cat, do you think it is clogged?

 

Yeah I do. Not completely but I get a low/rough idle in when I stop or put my car in reverse and I get a rattling sound under my car. The heat shield right on the Cat seems fine but it seems like its falling off on that curve.

 

It could be the heat shield rattling.
Can you get under the car & hit it to pinpoint the rattle?

 

Try shaking your muffler with the car off. I could be the heat shield between exhaust and driveshaft.

 

The heatsheild is basically that hall plastic covering? I think part of it is broken. The other part is stuck on by two metal zip-tie things. Looks like my heatshield is kinda broken. But I don't feel like my car accelerates the way it needs to. But I don't speed too much so that doesn't help.

 

 

Looked like the termite ate your Cat-converter

I guess you can drop it and see if you are clogged. Upload another video if you could.

 

wait what? That's just the heatshield though right?

 

What do you mean drop it? is that hard work?

 

Yea thats just the heat shield and the bottom of it at that. Its a fire danger but not a problem.

If you undue the 3 bolts on the front between cat and header. You lower the front of the cat and look in to see if you can see a small grid work or if it is clogged up.

 

It can be a fire hazard specially if it is clogged. I have spoken with another owner at a gas station awhile back and his engine caught on fire primarily because of a clogged cat.

ricocase, if both heat and rust contributed to the destruction of your heat shield I would consider looking at your Cat-converter, it surely terrified you, at least. Then when you've saved enough, have your ignition system replaced. Advanced Auto Discount Codes. I used these last year, not sure if all or some will apply to this year.

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