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08 check Malibu catalytic converter issues

Not directly.
Cat converter codes range from P0420 through P0438. They’re all directed around

  • catalyst efficiency
  • catalyst temperatures (warmup and heated).

There are different fault codes depending on

  • what bank the bad signal is detected, the condition of the catalyst warmup,
  • the temperature(s) of the catalyst(s)
  • the efficiency of the catalyst(s)

There is none that specifically tells you it’s your catalytic converter that’s bad. Determining that is up to the technician.

I’ve been arguing for the past few years that, with all the touch-sensitive menus that exist today there SHOULD be available to the car owner a readout the same as that one gets from a code reader, and perhaps even the capability for the car owner to access O2 sensor output scans, and even things like spark pulses. The stuff a scope or analyzer is used for. The capability is clearly there, it’s simply a matter of programming and having a decent display screen. That still would require some interpretation, but it’d be a giant leap for mankind.

But I need to remind myself that the purpose of OBD systems is not to help fix the car. Their purpose is to notify the driver that something that might affect emissions output has gone awry and the car needs to go to a shop for diagnosis. It’s about preventing emissions, not repairing the car.

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When I first got a car with OBDII I was a bit nervous if I could deal with it. Soon enough, I learned it was conceptually akin to what Military equipment called Self-test, and now I love it. True, it does not tell you exactly what the problem is, as we have seen in P0420 discussions. But, it certainly gives you a fighting chance in most cases.

Also, there is not a lot of information available without expensive subscriptions on exactly what each test is. For example, once I found a break-down on READY to test for the Toyotas, it really helped a lot. On military stuff, I usually had the entire software listing to dig through…

I have not even been sure if the engine computers are microprocessors, or something like PAL Programmable Array Logic. If I did run into this information, I may have forgotten it.

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I need to amend my own post. OBDII systems also tell the driver about safety problems… but only as they’re related to federal mandates.

I guess a better way to say what I said was to say that OBDII systems are not designed to help fix the car, only to notify the owner if the car violates federal emissions OR safety mandates.

Unfortunately, there is a whole host of safety things that happen to cars that aren’t related to mandates and the own has no way of knowing they’re there save common sense.
It’s further complicated by plenty of EVAP codes that few can figure out. I knew someone who bought a 1-year-old used Saturn from a Saturn dealer about 10 years ago that had the CEL illuminate a few months after purchase. The dealer never could fix it after countless tries and visits from the manufacturer rep.

Like I said many times before, my Rivieras allowed you to go into diagnostic mode anytime you wanted to. You just pressed two buttons at the same time on the CRT screen and you could see all of the computer readouts. O2, fuel trim, etc. etc. I can’t remember which buttons they were and the information was only in the factory service manual. When I tried out my 2nd Riv, with the salesman sitting next to me, I went into diagnostics to check for codes, oil pressure, trans solenoids, etc. Good as most cheap scan tools for OBD I. Every car car has it all built in, I believe, just a matter of being able to pull it out.

I can only imagine that being feasible on a select few cars, those with no rust, easy to access converters, and small units.If you look at the catalyst on a number of popular mainstream cars, like a Ford Taurus, Chevy Tahoe, or a Subaru Legacy, you’ll see that the catalyst assembly is large enough that you’d need a bathtub to soak them overnight. My wife would love that…

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The device in engine management systems is technically called a microcontroller. It takes very little horsepower in either hardware or firmware to do the job it does.

Believe it or not, the infotainment system often has a more powerful device that is an actual microprocessor, similar in capability to the processor in a desktop computer.

PALs aren’t used much anymore. They have been replaced by more capable devices like EPLDs and FPGAs that also can be programmed in-situ.

I personally consider this the equivalent of “hearsay evidence”. Until I actually can converse with someone who’s done this successfully, or see some official maintenance link by a qualified source, I believe it to be myth. “I heard that”, “I met someone who”, “I knew someone that”, to me are all buzzwords for hearsay. No disrespect meant to Irlandes.

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Can a cat be cleaned by burning something in the fuel? I put this firmly into the maybe column :wink:

I once owned a home that was primarily heated with wood burning stove(s). The prior owner had kept the chimney looking pristine by running very hot fires with well seasoned hardwoods. Shortly after I bought it, I managed to bump the thermostatic air vent control and essentially closed it. The result was quite a few days of smudge pot like fires. A really hard glossy creosote layer formed in the flue that was impervious to just about anything. Several chimney sweeps and chimney experts told me it was quite dangerous and- almost impossible to remove by any means short of mechanical abrasion. And the latter would likely damage the flue to the point I would need to replace it. Yikes!

What about those creosote logs, do they really work? I burned a case of them and saw little improvement. I researched the active ingredients and found many use simple TSP as the active ingredient. So I went and bought a tub of that. I was more generous in the application. Lo and behold, it started flaking off shortly afterward. It took a year but it cleaned up pretty good. I might have been a gold star customer of TSP but it worked.

Could a combusted chemical react with a carbon coating on a catalyst and cause it to be released? I think it could but don’t have any proof. And likely, it would take A LOT more than what you get in those tiny bottles they sell…