97 voyager - catalytic efficiency failure

Visit Topic URL to contact author (reg. req'd). Report abuse: When the upstream 02 sensor and downstream 02 sensor start switching at the same rate, that is telling you that the catalytic converter is not working and replacement is the only fix. That is how the cat efficiency monitor works

Glenn Beasley Chrysler Tech

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That is just the beginning of it. How many miles on this? I think it not likely that a catcon would fail in a 97 Voyager without some reason. Our 95 T&C has

110,000 miles on it and it's catcon is still going strong.

catcons fail because the fuel mixture going into them is wrong. Too rich and they get sooted up. Too lean and they overheat and burn up. Without finding the reason that this catcon failed, a new one will be destroyed in short order.

Ted

You have no idea that your cat is performing as well as you think. Your car is not equipped with an 02 sensor before and after the convertor to monitor its efficency. Convertors do go bad and they do wear out, if they can not store oxygen they fail the monitor and will will require replacement.\ Glenn Beasley Chrysler Tech

My 96 Grand Voyager catcon just failed at 167,000 miles. They can and do fail due to a variety of reasons. Erosion from the exhaust gas stream. Various trace contaminants in the fuel that add up over time, etc.

Maybe yes, maybe no. All depends on how many miles are on the vehicle (I don't remember if the OP said how many), how it was driven, etc.

Matt

Of course I know since my state has IM testing, every 2 years, and they give a nice printout of HC's and all that. And it is a tailpipe test with a dyno. And luckily they will do a free test on request.

Sure, of course it's not as good as the day it rolled off the assembly line, but it is nowhere near failed. My HC's are still close to the min for a vehicle of that engine configuration, or rather they were a year and a half ago when it was last tested.

I am not disputing that converters can die from simple old age. That is why I asked the mileage for the 97 Voyager, which wasn't supplied by the OP by the way. So in the absense of facts, we have to make some reasonable assumptions here.

Now, this is a 97 Voyager and average yearly mileage is

11400 (according to this: for a 97 Voyager a reasonable assumption is the OP's vehicle hasaround 90k on it.

That's just a bit young for a catcon failure when there was no other engine problems, don't you think? Espically when the Federal Emissions Warranty on the catcon is 80K. Are you telling me that Chrysler's design group has catcon designs dialed in so perfectly as to know down to the tenth of a cent exactly how cheap they can make the catcon to guarentee that it will just barely make it past the

80K mile mark, but not too much further past that? Sounds a bit farfetched! :-)

There's lots and lots of people who spend $$ for an expensive catcon to get through an emissions test, then a few years later the catcon is bad again and they are scratching their heads. We don't want the OP doing that.

Ted

There's a lot of testing that goes on to determine how to blend gasoline so as to NOT kill a converter. There are companies that do nothing other than manufacture and sell converter test apparatus, did you know that? This is something that the EPA cares about greatly. (for what should be obvious reasons) It is also paid close attention to by the automakers since the Fed requires them to warranty the catcon for 80K, and the last thing the automakers want are the oil companies selling a bunch of gasoline with phosphorous or other contaminants in it that will ruin the catcons which they will then have to replace.

I'll withdraw that for Canada, however, as that country seems to have an anything goes policy about gasoline.

I hope you replaced your O2 sensor at the 100K mark, if you didn't that is probably what killed your catcon.

Maybe you could have deduced that the OP didn't supply this when you read the sentence in my post "How many miles on this?" Would I have asked if the OP had supplied the mileage?

Are you really advocating that the OP simply slap a new catcon on his vehicle without checking to make sure the mixture is correct? Is that what you did? Espically when new catcon warranties specifically disclaim liability when the new catcon fails as a result of a fuel mixture problem?

Lets see now, a bit of Googling and quoting is in order here:

"catalytic converters fail, and the two most common reasons are clogging and poisoning."

"It is very important with emissions problems though never to replace the catalyst without checking everything else out first"

"If you do determine that your catalytic converter is defective, it is extremely important that you determine the reason for its demise"

(basic discussion of o2 sensor importance along with a chart showing change interval)

Ted

True, but you can't economically produce gasoline that is 100% free of contamination. Eve trace levels add up over time. That was my point. You seemed to be implying that unless something goes amiss with the engine, a catcon will last indefinitely. That simply isn't true.

Actually, my van has two of them and both were replaced some time ago.

They fail for other reasons also, that was my point.

No, I didn't advocate that at all. The problem should be properly diagnosed. My statement was only in response to your erroneous claim that a catcons only failure mode is due to incorrect mixture. That isn't correct.

You left out another important part of the quote. Here is the entire sentence: "There are many reasons why catalytic converters fail, and the two most common reasons are clogging and poisoning. A catalytic converter that is clogged may affect the performance and gas mileage of your Volkswagen. A poisoned catalytic converter, on the other hand, is the result of too much lead in the gasoline used for engine fuel."

Note the first part "There are MANY reasons...", with my emphasis added. This is exactly the point I was making. Incorrect fuel mixture is only one source of failure.

Matt

The car has about 200k miles on it. The flashing dash light gives me the codes: 12 - 33 - 72 - 55

- can anyone confirm what those codes mean? i.e. do they really tell us the cat. converter is dead and needs replacing?

- how long can a drive this thing before it does serious damage or quits?

thanks, Glen Flowers

Have o2 sensors ever been replaced?

Don't know that one, but maybe you can find it here:

There is also an article on there titled "Catalyst Efficiency Failures" might be interesting reading.

Ted

I was making a statement based on what I assumed the mileage was, and yes I implied that the OP's catcon shouldn't have failed. But that was based on an assumed mileage which I felt reasonable. Unfortunately that is the danger of reasonable assumptions, they are often wrong. Sigh.

In reality the OP's putting 25k miles a year on this van - quite a different issue.

Well, I don't really consider an age-triggered failure to be an unexpected maintainence expense. Anything that doesen't die prematurely due to defect or other outside influence is going to naturally fail at the end of it's service life. You can hardly expect otherwise.

Ted

There is no 72, try again, I would bet its 52 (02 sensor)

Actually, I'm pretty sure that 72 is the code that my 96 Grand Voyager flashed when the catcon went bad. The funny thing was, this code isn't even in the table of the FSM! However, when the dealer read it with the scan tool, it said the issue was catcon efficiency not being in spec.

Matt

Matt you could be right, I was told back in 96 that on the newer vehicles cycling the key was not an acuate way of retreiving fault codes, On the older vehicles 1994 earlier there was no such thing as a code 72

The MIL light did flash out code 72, but my code table in the factory manual didn't go that high. I found 72 via a Google search and it said it was catalytic convertor efficiency and this agreed with the scan tool at the dealer so I figured it was correct. And since replacing the converter, the MIL hasn't reactivated.

Matt