Questions tagged [catalytic-converter]

Device placed within the exhaust system used to catalyze pollutant gasses found in exhaust gasses. Is normally located after the exhaust header, but before the muffler. Can be configured as 2-way or a 3-way: the 2-way affecting hydro-carbons (HC) and Carbon-monoxide (CO) gasses; the 3-way affects Nitrogen Oxide (NOx - do not confuse with Nitrous Oxide or NO2) as well.

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11
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4answers
1k views

What exactly is a catalytic converter and why does it need to operate within a certain range?

I heard here that a catalytic converter needs to operate within a certain "chemical range" otherwise it will generate unnecessary heat. What exactly is a catalytic converter? How does it work? What ...
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1answer
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Engine misfires when car hasn't been driven for a couple of days

My 2001 Hyundai Elantra XD suffers from misfires during the first 5-10 minutes after starting the car. After this, the car runs as as it should. I'm not sure, but I think the misfires only happen when ...
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3answers
5k views

What's the purpose of having the cat right after the exhaust manifold

In a lot of the cheap cars I have looked at their exhaust components, I always find the catalytic converter right after the exhaust manifold instead of being after the down/front pipe in a "typical" ...
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0answers
605 views

Catalyst Temperature

Please refer to Catalyst Temperature PIDs (mode 01 pids 3C, 3D, 3E, 3F) for the following questions - https://en.wikipedia.org/wiki/OBD-II_PIDs#Mode_01 Q1. Is there a thumb rule that the catalyst ...
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1answer
539 views

Can a catalytic convertor be to small for an engine?

My car, a 2L BMW e34, failed its MOT on the gas test for CO readings. The tester said he thought it may be the cat had failed. I put a brand new exhaust system with cat and oxy sensor on my car, new ...
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2answers
6k views

Will eliminating factory catalytic converter have effect on emission testing?

I'm not exactly a car guy or know much about cars, but I would love to get some performance headers installed. The problem is that the headers that I found for my car state the following "Eliminates ...
6
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1answer
3k views

Incomplete Catalytic Converter Monitor on otherwise flawless old Tacoma

I have a 2000 Toyota Tacoma with 250k miles on it that runs like a champ. But, after some repairs, the catalytic converter monitor (or catalyst monitor) has never set. Every mechanic has told me ...
3
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0answers
939 views

P0420 Catalyst efficiency below threshold bank 1 With CO emission only!

I saw this code in OBD2 scanner on Skoda Fabia 1.2 2006 64hk petrol. It doesn't matter to me except that the car failed the inspection and I'm not allowed to drive it any more. The problem was too ...
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3answers
11k views

How can I tell if I have bad cats?

No, not that cat! Catalytic converters - or "cats" - have a nasty habit of failing with age. What are the symptoms associated with a cat that's gone bad? Are there any tests that could definitively ...
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3answers
21k views

Can A Catalytic Converter Fail Due to Age?

Suppose that a car has 120,000 miles on it and the catalytic converter fails. From what I read (see here as an example), age doesn't appear to be a general cause for failure. Is this a possibility ...
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3answers
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Check Engine code P0420 Catalyst efficiency below threshold bank 1

After months of normal driving with no problems, my 2003 Honda Civic EX check engine light came on during a long trip. Got it scanned and it's P0420: Catalyst efficiency below threshold bank 1. They ...
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2answers
2k views

Can a permanently stoich or lean running engine ruin a catalytic converter?

It's known a cat can be burned by an engine running too rich for too long, but i wonder what the effects are of constantly running lean. Will the cat just be uneffective because of the lack of CO, or ...
4
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1answer
332 views

On a 2004 Mitsubishi Lancer, Can a separated catalytic converter be re-attached to the exhaust manifold?

My question title pretty much covers it. This is a 2004 Lancer. The family car, not the sport version. These pics might help: Can this be repaired without replacing the whole unit? (That's an ...
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1answer
2k views

How could the code point to a faulty cat, when the O2 signals are normal?

I'm getting code P0420 on an '03 Vibe. The rule of thumb is that this means the catalytic converter is gone. Yet the pre- and post- cat O2 signals appear to indicate that the cat is doing its job. ...
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1answer
5k views

I just removed ALL of the catalytic converters on my 5.7l Toyota Tundra. Now What? [duplicate]

I'm not worried about the environmental/legal issues. I'm not too worried about the cel being on all the time. Do I need to do anything to protect my engine at this point? Thanks!
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1answer
835 views

Nissan Altima catalytic converter ruined twice in one month

My 2005 4-cylinder 2.5s Nissan Altima has been having major issues for the past several months. My mechanic replaced the catalytic converter and a month later another mechanic said that the catalytic ...
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1answer
66 views

Mode 06 approaching failure limit

In Mode 06 (OBD), one gets a current value, max value and a min value for every MID, TID supported. If the current value is out of the max/min range, that MID, TID is considered a 'Fail'. But there ...
7
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1answer
740 views

Locating the O2 sensors and the cat along the exhaust

I gather that the upstream O2 sensor is the one right in the center of this picture. I also gather that the catalytic converter (the "cat") is the bulbous part of the exhaust right behind this sensor. ...
2
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1answer
310 views

Car stalls on intersection or when coming to a stop

I have a 2000 Mazda 323F (some say it is Protégé but not sure) AT 1.6L (at 128K km). It runs smooth, accelerates great and shifts nice on most occasions. But there are times after running for a ...
5
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3answers
37k views

How do I fix P0431 Warm Up Catalyst Efficiency Below Threshold Bank 2

I just got my 2004 Mitsubishi Endeavor Limited 4WD back after 4 weeks in the shop, there was a problem with the transmission and $1800 later the transmission was completely replaced. I was driving ...
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3answers
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2003 Toyota Corolla, 185k: erratic OBD codes, fuel smell, other symptoms

TL;DR: O2 sensor data, thermal measurements, and physical resonance tests all point to a failed Catalytic converter. Here's the back story. MIL illuminated with codes P0440, P0420, P0404. Around this ...
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1answer
2k views

1998 Honda Civic - O2 sensor or catalyst failure?

I have the P0420 code on my 1998 Honda Civic DX (catalyst system efficiency below threshold bank 1). I want to be able to properly diagnose the problem myself without just throwing new parts at it. A ...
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1answer
198 views

Breaking in a new catlytic converter?

I read somewhere you need to break in a new catalytic converter. To that end: Is this accurate? What is the purpose of breaking one in? How do you break it in?
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2answers
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Bad Cat? Bad smell in Car when heating on [duplicate]

Have a 2004 Toyota Corolla with about 110,000 miles. When I ride the car with the heat on, every now and then it smells like rotten eggs. I looked online and people say I may have a bad catalytic ...
4
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2answers
4k views

How to install a California oxygen sensor into a federal catalytic converter assembly?

I have a 2000 Mitsubishi Galant ES 2.4L Engine with California emissions. Installed is a new federal catalytic converter assembly. The problem is that I do not know what kind of oxygen sensor to ...
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2answers
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2006 Scion Tc Base - lots of vibration and bad smell from exhaust

2006 Scion Tc base automatic transmission, has 149k miles on it.The car used to vibrate a little at idle. It suddenly started vibrating a lot. It is shaking as if there's an earthquake! Idle rpm at ...
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2answers
73 views

1980 Chrysler LeBaron Failed Emissions Test

My 1980 Chrysler LeBaron (V8 318ci) just failed an emissions test. I'm coming from a state without emissions testing to a state that requires it. Specifically, the only part that failed was the ...
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2answers
15k views

Will Driving 100 Miles With a Misfire Damage My Car?

Background: I have a 2002 Dodge Dakota Quad Cab slt with 4.7L Magnum V8. My check engine light came on when I was at work. I then drove 20 miles home to my house, pulled out my scan tool and ...
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2answers
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Half of my cylinders aren't firing. Is it safe to move my car to a garage (~30km)?

I am having some issue with my ECU or ignition system which I can't fix myself. Only two of my four cylinders are firing. Is it safe to drive my car to the official mechanic at 30km distance? Should I ...
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2answers
587 views

DPF (Diesel Particulate Filter) and Turbo: Golf TDI Bluemotion(hybrid)

I have a problem with my 2012 Golf TDI Bluemotion. The DPF and turbo need to be replaced. The replacement costs about R65 000 SA Rands. Is this common with this TDI blue motion engines or it's my ...
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2answers
4k views

How does push starting damage the catalytic converter?

In the manual for my 2003 Opel Agila it says: Do not start by pushing or towing, Your vehicle is fitted with a catalytic converter, it must NOT be started by pushing or towing. Why & how would ...
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2answers
147 views

1989 Nissan pintara problem

I have a 1989 U12 2.4l Nissan Pintara. It started running really rough one day and when I got home the exhaust manifold was glowing red hot. I changed the catalytic converter and it still is running ...
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1answer
2k views

2001 Elantra keeps throwing the same check engine light code

I replaced the main catalytic converter and manifold on my 2001 Hyundai Elantra, I believe it was last summer. A few weeks ago, I was on a long trip and the check engine light came on with the ...
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3answers
5k views

Will a universal catalytic converter set off the check engine light on an Infiniti G35?

I have a 2004 Infiniti G35 and the bank 2 catalytic converter has triggered the check engine light. If I replace it with a universal Magnaflow catalytic converter (approximately $100) will the check ...
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2answers
393 views

Can the catalytic converter from a 2005 VW Beetle be used in a 2004 VW Jetta?

Someone I know just seriously damaged their 2005 VW Beetle and it may not be worth fixing (drove over a divider and at least broke the transmission). The car has approximately 34k miles on it, if I ...
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1answer
1k views

Is it normal to attach a catalytic converter with U-bolts?

I need to replace my catalytic converter. The current one is held in place by U-bolts. Two U-bolts between the cat and the manifold exhaust pipe (looks like a patch). One holding the exhaust pipe to ...
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1answer
2k views

Can faulty O2 sensor cause omission check engine light?

I have had a check engine on a 2001 Subaru Legacy for some time now. Went to mechanic to fix few other things and he told me the oxygen sensor and catalytic converter needs to be replaced. The ...
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1answer
595 views

P0420 code for 09 Murano

I've had several opinions stating my car needs a cat converter but after failing inspection today, the mechanic said it might need ECT sensor changed. I've read previous posts that cat converters ...
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1answer
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Catalytic converter heat shield fell off .. Drive home or call tow truck?

One hour drive from home with family. Heat shield fell from 2007 Honda accord. Both top and bottom halves of shield rusted from corner bolt. Safe to finish trip and repair tomorrow, or is the ...
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1answer
1k views

Catalytic converter possibly bad. How soon do I need to replace?

2004 Cadillac SRX V8 AWD is making a rattling sound when idle, and mostly or completely goes away when RPMs increase. From what I've found, this is a bad catalytic converter. It is under warranty ...
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2answers
3k views

Catalytic converter readiness monitor never sets

I Reset the computer in my 1998 Chevy Astro, but even after driving around for a few days and putting it through the GM drive cycle, the OBDII reader is saying that the CAT monitor is not ready. I ...
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1answer
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What's the purpose of the cover on the catalytic converter?

On my 1990 Honda, it's falling apart. I'd like to just rip it off; will that cause any problems? More specifically: will the car pass New York state inspection with a missing cover?
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3answers
305 views

How much of the exhaust is the “cat-back”

My brother-in-law's car has just failed inspection. One of the items listed was a "cat-back." Since the bill is astronomical, I was wondering how much of the exhaust system is encompassed in this term ...
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1answer
7k views

What are the tell tale signs of a catalytic converter that might be going bad?

I've owned two vehicles whose catalytic converters were recalled due two a couple of reasons: one being the quality of the CC and the other being a reduction in power due to a material building up and ...