2001 ITR with 50K miles. AEM intake, DC 4-1, and an Apexi N1 catback. This has been the second time I have received a engine light with code 67 in only 3,000 miles. I have changed the cat already with a brand new one from Acura. Is there something in my engine causing the cat to go bad or is my o2 sensor jacked up?

 

if that code is related to the O2 sensor, then it sounds like O2 sensor to me, not the cat.

 

you bought a brand new cat??
omg

did acura tell you to do that? If so, I think they were trying to screw you for money

i have rarely heard of a cat failing at that milage

 

Modern cats should not rot out. And if its at 50K miles he should still be under warranty for emissions equipment.

 

Is the cat rattling or clogged? It's likely the sensor that's bad, especially if you're on the second one. I hope you didn't pay retail for the new cat, I sold mine w/ 25k when I put in a carsound for $60.

 

check your O2 sensor

 

You have an aftermarket air intake, header and exhaust. Cats are meant to handle a certain temperature range. If you are untuned, then you are running rich. With a better flowing header and exhaust you are pushing more out of your engine than you were before, throwing more unburnt fuel into the cat. When the cat can't handle the temps any longer (i.e., from running rich), the catalyst becomes seperate from the mat and/or the catalyst becomes burnt and useless, and you've effectively killed the cat.

Either that, or you have to take out your secondary o2 and clean it off. It could be totally covered in the same stuff that coats the inside of your header and exhaust.

Either way, when you have higher flow i/h/e, you need to tune or your cat will be unable to function properly due to higher temps from an increased amount of unburnt fuel. TUNE if you have mods and expect your cat to last, its the only way. Otherwise it is a crapshoot.

If you don't believe me, ask SMSP about this, he's posted about this numerous times.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">You have an aftermarket air intake, header and exhaust. Cats are meant to handle a certain temperature range. If you are untuned, then you are running rich. With a better flowing header and exhaust you are pushing more out of your engine than you were before, throwing more unburnt fuel into the cat. When the cat can't handle the temps any longer (i.e., from running rich), the catalyst becomes seperate from the mat and/or the catalyst becomes burnt and useless, and you've effectively killed the cat.

Either that, or you have to take out your secondary o2 and clean it off. It could be totally covered in the same stuff that coats the inside of your header and exhaust.

Either way, when you have higher flow i/h/e, you need to tune or your cat will be unable to function properly due to higher temps from an increased amount of unburnt fuel. TUNE if you have mods and expect your cat to last, its the only way. Otherwise it is a crapshoot.

If you don't believe me, ask SMSP about this, he's posted about this numerous times.</TD></TR></TABLE>

This is true, running too rich will kill the cat.

 

Actually, there is a optional recall(TSB) on the 2000-2001 ITR where the dealer replaces the wire harness and the O2 sensor, I would go to your local Acura dealer and have them look it up and have them replace it. The only difference is actually the wire harness(the part where the O2 wires branch off of the harness has a more secure zip tie).
I'll see if I can find the Technical Service Bulletin number.

Good luck!

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">You have an aftermarket air intake, header and exhaust. . . . If you are untuned, then you are running rich.</TD></TR></TABLE>

How does I/H/E make one run rich?

Even if it does there is no way it would burn out a cat in 3,000 miles. You have a problem with your O2 sensor.


Modified by fredtoast at 3:40 PM 6/11/2003

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by fredtoast &raquo;</TD></TR><TR><TD CLASS="quote">

How does I/H/E make one run rich?
</TD></TR></TABLE>

And no offense, but a AEM intake and DC sports header are not significantly increasing the breathing capacity of the motor

 

Maybe not 3000 miles, that's ridiculous.
But any time you have any modifications and you have an aftermarket cat, you are running the risk of burning up the cat if haven't tuned. Tell me that isn't true. Especially an aftermarket cat, but this doesnt exclude the stock cat.

I didn't say that I/H/E makes us run more rich. I said we are already running rich on the stock computer, the I/H/E just amplifies this since the flow is 'slightly' better than before. (you are right RJ, but it does change the flow somewhat, no?) It is a very common problem, people burning up cats from not tuning. Why do you think that happens? It's from running rich, the stock computer does that unless told otherwise. You can't deny that.

Maybe my statement was vague or worded incorrectly, but I still believe it was fairly obviously what I was trying to say.

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote &raquo;</TD></TR><TR><TD CLASS="quote">You have an aftermarket air intake, header and exhaust. . . . If you are untuned, then you are running rich.</TD></TR></TABLE>

The way you quoted me incorrectly reflects what I was actually saying. Leaving out a sentence or two and running those two sentences together really changed the meaning.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Chris N &raquo;</TD></TR><TR><TD CLASS="quote">Either way, when you have higher flow i/h/e, you need to tune or your cat will be unable to function properly due to higher temps from an increased amount of unburnt fuel. TUNE if you have mods and expect your cat to last, its the only way. Otherwise it is a crapshoot.</TD></TR></TABLE>

Why would unburnt fuel cause an increase in exhaust temp.? I know that lean combustion will increase exhaust temps., but I don't understand how the byproduct of rich combustion will increase exhaust temps. I'm not trying to be an ***. I'd just like an explanation. Thanks.

 

I was always under the impression that after performing the I/H/E, one would have the tend to run lean if any change at all. In theory a better intake means more incoming air, header and exhaust "extracts" the air from the cylinder better so the bottom line is you get more air for more complete combustion. But the ECU should be able to compensate for the changes and optimize the air fuel ratio to whatever it was programmed to...

Running too rich means there would be enough fuel in the exhaust to start collecting on the material in the cat and eventaully "light off" which isn't a good thing.

As stated before, running rich will kill a cat because it just about sets fire to it and that will throw a code, as will a bad 02 sensor...

--
George

 

Thanks guys. I don't think I am running too rich or too lean with the bolt ons I have. I do belive my o2 is the cause, which is under warranty. And NO I did not pay full price of $8XX for a brand new factory cat. That is ubder warranty also. For those of you who don't know, emmisions related components are warrantied for 8 years/80,000 miles.

 

when you do an I/H/E, what is the cheapest way to tune the ECU?

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by 2qwik2nv &raquo;</TD></TR><TR><TD CLASS="quote">when you do an I/H/E, what is the cheapest way to tune the ECU?</TD></TR></TABLE>

Hondata/SAFC + Dyno time

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by .RJ &raquo;</TD></TR><TR><TD CLASS="quote">

Hondata/SAFC + Dyno time</TD></TR></TABLE>

HAHA...that alone cost more then the aem, dc header, and apexi n1 he has. you guys are just telling him to waste his money, just buy a high flow for 60 buxs and get a new o2 senser for about 40 buxs and your set.

 

<TABLE WIDTH="90%" CELLSPACING=0 CELLPADDING=0 ALIGN=CENTER><TR><TD>Quote, originally posted by Ch33se &raquo;</TD></TR><TR><TD CLASS="quote">

HAHA...that alone cost more then the aem, dc header, and apexi n1 he has. you guys are just telling him to waste his money, just buy a high flow for 60 buxs and get a new o2 senser for about 40 buxs and your set.</TD></TR></TABLE>

WHere are you getting a high flow cat with flanges made to length for $60? and an O2 for $40?

Best I woudl think is $120 for the cat and $100 for the O2. but this is guessing ballpark.

ANd telling him to tune isn;t wasting his money since if he is burning up cats and he doesn't tune he will keep replacing them. Why not make more power and not ruin parts while doing it?