Hot answers tagged

9

Looks like part of the muffler to me. You should have it replaced it could end up obstructing the exhaust.


8

The lack of a heat shield is not an imminent hazard. You do want to take a few precautions. First do not park over any flammable objects such as grass, leaves trash etc. Don't place anything on the floor above the converter that may be damaged by the heat like a laptop, digital camera.


7

If the cat rattles (may happen more after warmed up), then it's definitely bad. Banging on it can help see if there is material loose in there. If the cat was plugged up enough to affect performance, I would hope that one of the 02 sensors would kick off the check engine light. However, if it's borderline, I guess the engine may be able to adjust the fuel ...


7

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

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 ...


6

The cat back is just that the exhaust pipe including the muffler from the catalytic converter to the end of the tail pipe. Seems odd to me, not impossible just odd that you would need to replace the entire exhaust system from the cat back to pass inspection. I see from your profile that you are from PA and road salt can deteriorate an exhaust in that ...


6

It was indeed the catalytic converter (the EX does not have a pre-cat). After replacing it, the downstream sensor graph spends most of its time above 0.5 V, as it should if the converter is working. Update: I started getting this error code again, a little over a year after replacing the cat. I also finally found a guide on how to read these graphs, from ...


6

Looking at the description of the California O2 sensor for your car, the only thing different on it (besides the internals) is the electrical plug. The wrench which you tighten it down with is 7/8", which means the sensor bung should be the same size as well. I don't think there is any real external difference between the California and non-California ...


6

According to this website, the cat can surely be plugged by coolant entering the catalytic converter. Here are the reasons given on the website: Engine Tune-Up Required. A number of problems could occur to the catalytic converter as the result of an engine that is out of tune. Any time an engine is operating outside proper specifications, ...


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 ...


4

I found pretty good video about changing the muffler here. As Larry said, it is not the catalysator but the part before the catalysator. It looks like something that even an amateur is able to do. In Finland, the cost is about 60EUR for the part so not expensive part. (source of the image) Terminology muffler = äänenvaimentimet, takapönttö ...


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

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.


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

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

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 ...


3

If the catalytic convertor is truly plugged, you wouldn't be able to drive the vehicle, so this makes me wonder about the voracity of your statement. With a plugged cat, the back pressure created behind it will only let you rev the engine to around 1500-2000 rpm. I had to replace a set of heads on a pick-up truck for a guy because he continued to run the ...


3

Is it normal to attach a catalytic converter using u-bolts? Or when i replace it should I have it welded? It is not normal to utilize u-bolts (muffler clamps) on catalytic converters. They are most often welded in place.


3

Based on the link provided, I assume the ~400$ piece looks like 2 converter based on original equipment(OE) design, or as when the car came out of factory. Those at ~40$ looks more like an aftermarket replacement, with 1 converter and some installation required (welding and exhaust modification) while the OE is bolt-on.


3

I can't tell you if it'd fail inspection or not, but there's a good reason for its existence. It's basically a heat shield that protects the body of the car and the carpet/sound deadening in the car from the heat of the cat. Catalytic converters can get very hot (in the worst case, glowing hot) and without the heat shield that can cause problems or at least ...


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 ...


2

Newer cars (1996 and later) have additional catalyst agents than the old cars had. $100 sounds like one of the old car cats. $500-1000 is more in the ballpark where the newer cats are typically found. Will an old cat keep your light off? Perhaps. Perhaps not. Is it a legal replacement, no, not from what I remember of the federal code.


2

It sounds as if the internals of the cat may have broken loose. The catalytic converter is already broke so you can't make it any worse. The worst thing that can happen is it could the piece that is rattling may break free and plug the exhaust leaving you stranded. I would also ask the dealer if they will cover potential problems of a clogged muffler later ...


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 ...



Only top voted, non community-wiki answers of a minimum length are eligible