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11

A catalyst is a chemical that contributes in a chemical reaction but remains unchanged after the whole reaction is complete. In a catalytic converter platinum is the catalyst that converts unburned hydrocarbons into H2O and CO2. If there is too much unburned hydrocarbons going into the catalytic converter, it greatly increases the temperature inside the ...


8

Cats can stop functioning in a couple of ways: physical deformation due to high temperatures According to this article, the catalyst melts at temperatures above 2100 °F (1200 °C). In the event of a meltdown, the catalyst gets permanently damaged, at which point it doesn't scrub the nastiness out of the exhaust gases and serves as a major exhaust ...


7

This website seems to answer all of the questions you have asked above. http://www.easterncatalytic.com/education/tech-tips/proper-break-in-can-prevent-future-problems/ The website discusses proper procedures to make sure that the catalytic converter is broken in correctly. At the bottom of the article there are steps to break in the catalytic converter. ...


7

Even before a cat plugs, you can test your cat using a laser thermometer. You are looking to compare the inlet and outlet temps on your cat. Do the following: Run the engine up to operating temperature (at least ten minutes so the cat should be fully warm) Check and record the inlet temperature. You're looking to measure the temperature right where the ...


7

Picture 1 is the downstream 02 sensor. Upstream is located on the exhaust manifold. Picture 1 contains both convertors. Picture 2 is the exhaust resonator.


6

A catalytic converter incorporates a structure that is coated in precious metals. When catalytic converters first came out that structure was ceramic balls coated in the metals. This didn't work so well and the structure was changed to either a honey comb or a monolith, both ceramic. The tubes of the honey comb run the length of the converter. A monolith is ...


5

Just to add to the other answer as I ran into this same issue, what kind of emissions do I have on my mitsubishi galant? I had this code: P0421 and I had to replace my O2 Sensor & the catalytic converter but I wasn't sure if I needed the CARB (California Air Resource Board) compliant ones or not. There is a label that identifies what type you have. I ...


5

If you have rattling on acceleration and the fuel economy is depressed, it is very likely that the catalytic converter core has cracked and it is blocking the exhaust now. You can try to measure its efficiency first by looking if the rear O2 sensor voltage reading after heating is steady (so the catalytic converter is good) or jumping (so it is bad). If it ...


5

Excellent graphs. The after catalyst sensor shows normal mixture readings. The PCM can and will operate the system lean or rich depending on operating conditions. The voltage will rarely be held at any intermediate voltage, such as 0.5 volt. This is an urban legend not based on engineering fact. The rear sensor voltage should remain steady at any steady ...


5

I suspect that this is caused by one of two things although it could be a few more. It is most likely a sticky ISV. The ISV or Idle Stabilization Valve is responsible for allowing just enough air through the engine to keep it running when the throttle pedal is being pressed. If this is faulty, the car will run perfectly until you take your foot off the ...


4

Has Service bulletin EG028-04 been performed? This TSB reprograms the ECU so the fuel mixture is set closer to Stoichiometric and slightly to the lean side. The TSB suggests a new catalyst, We have done lots of these without replacing the catalyst. The rotten egg smell from the exhaust is caused by the catalyst releasing hydrogen sulfide gas. This happens ...


4

If an exhaust restriction is suspected a pressure gauge pre-catatlyst works just fine. My maximum cutoff pressure is 1.25 psi but most good systems will be well below that. The intake manifold vacuum is also a good clue. If it is not close to the idle reading at 3000 rpm suspect an exhaust restriction. In the case of a restriction the vacuum reading will be ...


4

All of this comes from: http://auto.howstuffworks.com/catalytic-converter2.htm Ok, attacking each of these in order: What exactly is a catalytic converter? It is a device in the exhaust path of your car that scrubs unwanted gases from the exhaust stream. How does it work? In chemistry, a catalyst speeds up a chemical reaction without actually taking ...


4

tl;dr: I can't find any evidence that removing the catalytic converters on this model will improve the car. It will definitely confuse the ECU (and obviously pollute more). I've looked hard for any dyno sheets that show any concrete evidence that cat delete alone will add power. Removing the cats is something that I would almost never recommend outside of ...


4

unburnt fuel can damage the catalytic converter. By tow starting the car you could cause large amounts of unburnt fuel to be pushed through the engine and into the catalytic converter.


4

I would personally avoid it as you'll be putting some very odd stresses on the engine and the heat generated will be non-uniform too. For the sake of arranging recovery or even finding a friend with a straight bar or even just a sturdy piece of rope, I don't think it's worth potentially ruining your engine.


4

In short: no. To pass smog in California (and other CARB adopting states) the catalytic converter must be the one from the dealership or one that is in the Aftermarket Catalytic Converter Database. The catalytic converter must be one of those listed for the Toyota Prius, but unfortunately there is none for the Prius. For now the only possibility is to try ...


4

You should be fine. Though I would recommend unplugging the connector to fuel injector #7 to minimize the amount of unburnt fuel that makes its way to the catalytic converter.


3

This is counterintuitive: Lean mixtures at high exhaust flow rates can damage a catalyst. The most common condition for this is the engine running out of fuel. But push starting could put the catalyst in the same condition. How this works it that the lean mixture does not burn in the cylinder but does in the catalyst if it is hot enough. It is the same ...


3

The DPF or Diesel Particulate Filter is part of the exhaust system the Turbocharger pulls it's power from the exhaust system so it in conceivable that a blocked DPF filter could stall the turbocharger causing damage. Also, a failed turbocharger could dump lots of oil into the DPF which would be equally damaging. We have a 2012 1.6 TDI Bluemotion Golf and ...


3

• Why does it need to operate within a certain chemical range? The gasoline engine catalyst feedgas (exhaust gasses) must remain in a very small window of fuel mixture because the chemical reactions the that reduce NOx and oxidize hydrocarbons are mixture dependent and mutually exclusive. NOx can only be reduced in a fuel rich environment and HC can only ...


3

It definitely sounds like you have a serious issue with the catalytic converter and should have it replaced. Replacement with a universal converter should not be expensive. In expensive Silicon Valley (and air conscious CA) I got a replacement for $220 at a specialist shop. However, the failure of your catalyst is a symptom of another issue and not a cause, ...


2

Essentially the technical meaning of a p0420 is that the downstream o2 sensor is detecting an inconsistency with fuel trim. Generally this is code is associated with a bad catalytic converter. Many things can cause this code, but usually the easiest ways to figure it out are testing it with a hydrocarbon analyzer. The dealership usually has one of these. If ...


2

If the smell is from the internal heating system and not from the exhaust system then this is likely to be due to organism (mould, bacteria, ...) growth in the air distribution ducts and heater. This is a well known problem. Proprietary products are available that are intended to cure this problem and adds are some standard household products will work in ...


2

The DPF is basically a catalytic converter for a diesel engine. I wouldn't say it's necessary that both of these things fail at the same time, but it's possible. I will assume you do lots of short trips rather than regular long trips? At any rate, the DPF needs to periodically heat up and stay hot for a long period to burn off excess deposits. A nice long ...


2

The catalytic converter is there to make your exhaust cleaner. It does nothing critical to the proper running of the engine itself. If you remove it, all that will happen is that you'll get dirtier exhaust and an error code P0420 (Catalyst System Efficiency Below Threshold (Bank 1)), which is to be expected because the "catalyst system" has been removed. ...


2

With the P0422 code, it can either be the O2 or the cat which is bad. Do as @JuannStrauss said at first and see if you can clean the O2 sensor. You don't do this by taking it out, but rather running some cleaner through the engine. My preferred method for this is a SeaFoam treatment. If that doesn't fix your ills, you need to figure out if your cat is ...


2

While you have that spark plug out, i would highly recommend doing a compression check on that cylinder while you have everything off/out.


2

Beneath the stress mentioned by @SteveMatthews, there is another problem. A larger amount of unburnt fuel in your exhaust system will damage your catalytic converter. I guess driving 30km with just half the cylinders fireing will be enough to kill the converter.


1

Try a junkyard/recycling center before buying the part new. You can find one in good condition for much less. If you want a new part, ordering it online is usually cheaper. This is not something that the dealership needs to do. Have your mechanic remove the old and install the new. Then delete/reset the codes. Has your mechanic tested the O2 sensors?



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