Stack Exchange Network

Stack Exchange network consists of 174 Q&A communities including Stack Overflow, the largest, most trusted online community for developers to learn, share their knowledge, and build their careers.

Visit Stack Exchange

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 ...

0
votes
0answers
22 views

Lambda high and positive ltft

I'm having a slight issue with a 2003 Z20LET engine in a vx220 turbo. The car is having emissions trouble with a high lambda reading. A few months ago when it had MOT the tester said it was very hard ...
2
votes
0answers
25 views

Hi CO Emissions - Kial Soul+ 2.0L

My 2012 Kia Soul+ (53,700 miles) failed the emissions test for high HC and high CO at high RPMs (2500). After a new air filter, spark plugs, a professional injector and throttle body cleaning, the ...
2
votes
0answers
16 views

California CARB converter list by the CA Air Resource Board is no longer available

The only CARB listed converters by California is AP Exhaust 749233 Direct Fit and 740566 single replacement are no longer available. I called AP Exhaust and they are closed down and not sure if they ...
1
vote
2answers
46 views

Mechanic is recommending new catalytic converters. Are these temperatures that bad?

I failed a smog test in CA (1992 Corvette) and the results came back that the EGR valve is not holding pressure. It failed on nitric oxide emissions measured at 989 ppm at 15 mph and 1329 ppm at 25 ...
0
votes
0answers
229 views

Is there much benefit from removing catalytic converter? [duplicate]

This is a different question, that question is asking about the implications for an ecu after removing cat. I'm asking why people remove the cat to begin with and specifically what sort of bhp gains ...
2
votes
1answer
33 views

Interpreting secondary O2 values

The vehicle in question is a Piaggio Porter, make and engine data are unavailable atm. The car was in really bad shape before the repairs: missed oil changes, oil consumtion, heavy soot contamination, ...
-1
votes
1answer
58 views

Why does my car sound like it has no catalytic converter when it hasn't been removed?

Well, my car suddenly started making a sound like if the catalytic converter was removed, which it has not. The noise started when my husband connected the a/c compressor directly to the battery ...
3
votes
2answers
94 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 ...
2
votes
2answers
47 views

Putting the wrong fuel stabilizer in a motorbike

Say that a friend had been silly enough to skim the text on the bottle of fuel additive, before mixing it into a full tank of fuel for his 40'000 km kawazaki z750. And say that it turned out this ...
2
votes
0answers
261 views

Smog test not passing

I need to get my smog check to pass and when I went to the test center they said it wouldn’t pass because the “catalyst converter” is “not ready” (this is what they showed me on their monitor attached ...
3
votes
1answer
136 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 ...
2
votes
4answers
3k 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, ...
4
votes
1answer
62 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 ...
5
votes
1answer
540 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 ...
2
votes
0answers
46 views

Corolla exhaust + converter replaced: engine check comes on

About half a year ago I had to replace the front part of the exhaust on my 2003 Corolla. SInce on this model it is welded to the cat converter, it had to be replaced too. Shortly after my local ...
2
votes
0answers
435 views

Catalytic Converter: To What Degree Is It Self-Cleaning?

The title says it, almost. With the exhaust passing through the catalytic converter comes a lot more than just the exhaust gas itself. Carbon particles, greasy slime, you name it - all the stuff that ...
1
vote
2answers
916 views

P0430 (Catalyst System Efficiency Below Threshold) Toyota Camry 2005 V6

I have a 2005 Toyota Camry V6. The check engine light was on for while and I cleared it once using an OBD2 reader. It didn't come up for while. I used the .87 petrol and I thought that is what ...
3
votes
0answers
66 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?
2
votes
1answer
700 views

Broken catalytic converter 7 engine damage

I have a 2017 vehicle that after 2,500 miles had the check engine light go on and went into limp mode. After 3 times in 2 different dealerships, it was diagnosed with a broken catalytic converter. I ...
3
votes
2answers
11k 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 ...
1
vote
1answer
36 views

My 2002 Chevy Impala

Good morning and happy mothers day to all the MOM'S. I have a 2002 Chevy Impala and some months ago I noticed my gas mileage wasn't as good as it used to be. The check engine light never came on. ...
1
vote
1answer
58 views

Why have to concentrate on exhaust gas instead of inlet mixture in Indian Bikes for emission control [closed]

I am having Apache RTR 180 (carburetor version) . Having a question towards Bharat Stage (BS) (Emission Norms) against bikes. Recently went through BS specification. To achieve this, we are going ...
6
votes
3answers
1k 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 ...
3
votes
2answers
5k 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
0answers
374 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 ...
10
votes
3answers
4k 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" ...
3
votes
1answer
177 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 ...
4
votes
2answers
3k 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
votes
1answer
1k 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
votes
0answers
559 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 ...
4
votes
1answer
2k 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 ...
7
votes
3answers
7k 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 ...
6
votes
2answers
1k 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
votes
1answer
164 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 ...
2
votes
1answer
2k 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!
5
votes
1answer
898 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. ...
8
votes
6answers
96k 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 ...
3
votes
1answer
554 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 ...
4
votes
1answer
49 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
votes
1answer
529 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. ...
11
votes
2answers
1k views

How does raw fuel damage the catalytic converter?

I was wondering, if fuel gets in the catalytic converter, how does it damage it?
2
votes
1answer
136 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
votes
1answer
1k 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 ...
8
votes
1answer
119 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
votes
3answers
1k 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 ...
11
votes
4answers
973 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 ...
4
votes
2answers
710 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 ...
15
votes
3answers
8k 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 ...
5
votes
2answers
4k 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 ...
0
votes
2answers
1k views

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 ...