97 voyager - catalytic efficiency failure

OK, so the "service engine soon" idoit light came on. So I paid the
local Merchant’s Tire $98 just to tell me i have a catalytic
efficiency failure. Now they want some $300 or $400 more to complete
the diagnosis.

I’m thinking they’ve gotta be kidding, right?

1) Is there some other way to find out what’s really wrong?

2) Is the car in any real serious trouble or is it just some nuissance
thing?

Thanks for any advice...

Glendon

 

http://www.autoforumz.com/eform.php?p=626977

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

 

need a new cat. converter

 

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: http://www.eia.doe.gov/emeu/rtecs/chapter3.html)
thus for a 97 Voyager a reasonable assumption is the OP's vehicle has
around 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:

http://www.partstrain.com/ShopByDepartment/Catalytic_Converter/VOLKSWAGEN

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

http://www.carclinicmagazine.com/renault_common_ecu_failures.html

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

http://www.all-catalytic-converters.com/techtip2.html

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


http://www.bondauto.com/interior.php/sid/5/aid/40

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


Ted

 

nice try but i replace them all the time for this code abd if it's a
driveability causing failure there is other dtc to check out usually

 

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:

http://www.troublecodes.net/

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

 

just like i stated hmmmmm