Okay people, so after less than 5000kms my catalytic converter failed and since I'm fairly new to cars and equally new to money, I'm seeking some advice before I go ahead and replace it to likely have it fail again.

 

The details:

- The car is a KE70 with a 4AGE bigport

- The engine is standard apart from the 4-2-1 headers and 2" zorst.

- The catalytic converter is straight after the headers, there's probably 2 meters of headers between it and the engine.

- The catalytic converter is a Lukey brand, ceramic type.

 

What happened:

- The car developed a weird rattle, then I discovered the rattle was coming from the cat, then recently it became very loud and annoying. Plus sometimes it smells funky

 

What could have cause it, these are the only things I can think of that may have caused it:

- I ran some LiquiMoly injector cleaner through it about a month ago, the bottle said it was safe for use with catalytic converters

- I did put some of that shitty 10% ethanol fuel in it once

- My AFRs could be wack, and it does smell like it's running rich.

- I occasionally rev the shit out of it, and I did drive up a twisty hill for a good minute with the engine constantly between 4000 - 7000rpm.

 

 

The cat is still under warranty, but to get a new one I have to pay for the replacement initially, get it fitted and have the old one removed (it's a weld in unit), then send the old one back to Lukey for a warranty claim, they check it out and then they refund me the money that I initially paid for the new one.

OK so that sounds like a shit idea considering the first one failed in about a months worth of driving. So that brings me to why I'm posting this thread.

 

What I want to know:

- What brand and type of cat are you running in your car? I'm thinking of going with a Magnaflow.

- Do metallic cats handle heat better than ceramic cats?

- Is it likely that having a rich AFR killed the cat (lol) and should I install an AFR gauge?

- If the answer to the above question is yes, is it worth while getting a wideband or will a cheapo narrowband do the trick? (there's a narrowband sitting at work at the moment on clearance for $20 and I'm considering buying it)

 

Sorry for the long post.

 

 

 

tl;dr: What is a good brand of catalytic converter and should I get a wideband or narrowband AFR gauge?

Edited October 9, 201313 yr by rian

I'm not evwn using one. Problem solved ;)

I'm using a narrow-band, I'm used to it and it makes sense to me. Until I see a wide-band working I don't know what the difference is. It covers from 14.7 down to 11 and up to 20, and once it is warmed up after a minute or two it is quite stable. I think the changes are faster in the narrow-band, so it flicks from 14 to 18, then sits there on constant throttle. When you touch the throttle next it changes very fast again.

 

The damage to the cat sound like mechanical damage, not chemical contamination, if it rattles. The alcohol fuel should be fine in it, I haven't heard of it affecting other cars.

 

As everyone knows, if it was me I'd be down at the wrecker buying the biggest, cheapest cat there...

I personally would just put it down to a faulty cat convertor. If it has been dropped between the factory it was made in and your car, then that would explain it. esepcially being ceramic, ceramic is brittle.

 

The cat i bought for my car was a "high flow" item from the exhaust shop. it was around $200. where the non high flow was 140ish i think.

I'm not evwn using one. Problem solved ;)

 

You know how big the fine is for that right?

 

I'm using a narrow-band, I'm used to it and it makes sense to me. Until I see a wide-band working I don't know what the difference is. It covers from 14.7 down to 11 and up to 20, and once it is warmed up after a minute or two it is quite stable. I think the changes are faster in the narrow-band, so it flicks from 14 to 18, then sits there on constant throttle. When you touch the throttle next it changes very fast again.

 

The damage to the cat sound like mechanical damage, not chemical contamination, if it rattles. The alcohol fuel should be fine in it, I haven't heard of it affecting other cars.

 

As everyone knows, if it was me I'd be down at the wrecker buying the biggest, cheapest cat there...

 

Thanks for the info there Altezzaclub. OK so a narrowband sounds like it should do the trick, I guess I don't really need to know what the AFR is I just need to know if it's lean, rich or stoich. The $20 unit from work should do the trick.

 

I personally would just put it down to a faulty cat convertor. If it has been dropped between the factory it was made in and your car, then that would explain it. esepcially being ceramic, ceramic is brittle.

 

The cat i bought for my car was a "high flow" item from the exhaust shop. it was around $200. where the non high flow was 140ish i think.

 

Yeah, I called the company that I got it from, the guy I spoke to was super nice. I didn't want to do a warranty claim on the shitty ceramic Lukey cat so he said he would do me a deal on a 200 cell metallic 2" Redback cat: $85 instead of $140.

I'm still annoyed because I now have to spend more money on another cat and then pay someone to weld it in.

I think that its a possibility that constant rich conditions ie excess fuel causes them to burn out.

Wideband all the way, its not just the sensor but also the processing unit...