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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16
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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 ...
12
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1answer
6k 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 ...
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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 ...
11
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3answers
18k views

Is the catalytic converter broken? An odd rope is coming out of the exhaust pipe

Old Volvo GL 440 and this is coming out of the exhaust pipe. No noise, all working fine but this cosmetic thing: does it mean that the exhaust gases are now not well filtered out? Does this mean that ...
11
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2answers
2k views

How does raw fuel damage the catalytic converter?

I was wondering, if fuel gets in the catalytic converter, how does it damage it?
11
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3answers
102k views

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 ...
10
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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" ...
10
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1answer
6k views

Can a head gasket leak cause the cat to plug?

Well, like the title reads ... I replaced the heads on a Dodge Ram V8 5.9L gas engine. It's now running like the cat is plugged. Can blowing the white plume of coolant exhaust out the tailpipe cause ...
8
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6answers
137k views

Is it a good idea to remove the catalytic converter?

Some people have suggested that I remove my cars catalytic converter. This is because my car is designed for a different market, and the manufacturer recommended fuel is not sold in my area. It is ...
8
votes
1answer
193 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?
7
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3answers
20k 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 ...
7
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1answer
2k views

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 ...
7
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3answers
2k views

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 ...
7
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1answer
730 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. ...
6
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3answers
3k views

Coolant in the cat, can it be saved?

The catalytic converter on a 2007 Mazda RX-8 is full of engine coolant. Is there any way this can be saved or do I need a new cat? It seems to me that coolant won't melt the cat like unspent fuel or ...
6
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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 ...
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 ...
5
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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 ...
5
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2answers
6k views

Can a universal catalytic converter be legally fitted to my Prius in California?

My 2006 Toyota Prius with 280k miles is throwing the P0420 code, which means that it (probably) needs a new catalytic converter. I live in California, which makes life much more difficult to replace a ...
5
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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 ...
5
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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 ...
5
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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 ...
5
votes
1answer
35k views

How long will my motor last having clogged catalytic converters?

My catalytic converters have been clogged for awhile, and the o2 sensors need changed because of this. What is it doing to my engine? And gas mileage for that matter? If i take out my ...
5
votes
1answer
12k views

How to determine if P0430 is O2 or catalytic converter

2009 CTS4 3.6L P0430 catalyst below efficiency bank 2 comes on periodically. (There are no other codes being thrown.) I put a data logger on it today on my drive to work and the rear sensor is ...
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 ...
5
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1answer
4k views

02 sensor displays constant 3.3 volts, not a jagged waveform. 2002 rav4

Got P0420 and P0430 codes, suggesting the catalytic converter needs to be replaced. Everything I have read suggests the wave form after the cat ( sensor 2) should be a delayed version of before the ...
5
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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. ...
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 ...
4
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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 ...
4
votes
2answers
9k views

Removing catalytic converters on a 2000 v6 Mustang?

I live in Oklahoma, so we don't have to get emissions checked. I have a 2000 v6 3.8l Mustang. I bought the car for $3500 at 70k miles (it was a really good) so I don't want to spend more money than I ...
4
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2answers
1k views

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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1answer
5k views

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 ...
4
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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 ...
4
votes
1answer
315 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 ...
4
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1answer
80 views

Cat Converter Replacment & Sensors

I recently got a check engine light telling me that the O2 sensors had issues so I replaced them. The problem persistent, took it to make dealer and told it was the AF Sensors. I then replaced those ...
4
votes
1answer
65 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 ...
3
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2answers
583 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 ...
3
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3answers
23k views

Can a car operate without a catalytic converter?

So I was reading this Quora question which answers in the affirmative, but here's my misgiving: I was under the impression that the oxygen sensor which the ECU uses to adjust the fuel-to-air ratio, is ...
3
votes
4answers
11k views

Trying to Understand Post Cat O2 Behaviour During a Misfire

I've been researching using pre and post cat O2 waveforms to diagnose misfires and ran across this quote from the article, Intermittent Engine Misfire Analysis: Keep in mind that the downstream, ...
3
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1answer
1k views

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?
3
votes
1answer
383 views

Should I replace my Catalytic converter?

My 2007 Xterra had the P0420 code pop on. My understanding is that it most likely that the Catalytic converter is going out. If this is the case, how high of a priority is it to fix? Before you ...
3
votes
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 ...
3
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2answers
1k views

Why does the price of Catalytic Converters vary so much?

My check engine light came on and the diagnostic code says it is a problem with the catalytic converters so I'm getting ready to schedule an appointment with a mechanic to take care of that. The ...
3
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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 ...
3
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2answers
204 views

Is my catalytic converter bad?

I have a 2006 Lexus LX 470 and I’m getting the check engine light on. I have a reader and I am seeing P0430 “ catalyst efficiency below normal (bank 2). I took some data from the sensors and plotted ...
3
votes
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 ...
3
votes
2answers
9k views

Welding, Repair, or Patch Catalytic Converter Crack

I got rear ended and the exhaust pipe was mashed forward causing the crack in my Catalytic converter's weld. Or perhaps, it just worsened the crack if it was too small to notice before. The crack does ...
3
votes
1answer
824 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 ...
3
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0answers
158 views

Nagging P0430 (and now a pending P0420 too!) 2004 Lexus ES330

I've got a 2004 ES330 (2nd owner) with roughly 315,000. We didn't pay much for the car in 2012 with 164,000 miles. So, i've never gone overboard in maintenance of it. A year ago, when it was time for ...
3
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0answers
165 views

why can't catalyic converters mailed to california

Why doesn't California let other states ship converters to us residents? I'll have to pay outragest ca prices?