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billsimi 09-19-2016 07:24 PM

Catalytic converters?
 
I'm trying to figure out what could have happened to my catalytic converter. We have a 2004 Sea Breeze LX with under 37000 miles, since last January we have been trying to Pass California emissions test. This was its first failure since new, the first time we thought it was because it had sat for almost three months, so we took it for a camp out (300 mi.) trip and it failed again. New O2 sensors (Non OEM) failed worse. I returned them and ordered OEM O2 sensors, failed still. replaced MAF sensor check everything, ECM and its wiring. Did find and fixed a exhaust leak. OBD II has never shown a code, graf. for O2 sensors bank 1 was off but fixed after exhaust leak repair. Still failed.
Today I took off both catalytic assemblies and found to my surprise one cat I can see and it looks OK to me, and it is the one that showed a bad O2 sensor. The other one seems to be missing? I can see straight through the whole pipe.
We did have a front tire blow out on that same side last year while on the freeway, I don't know if it was hit by anything then.
Any guesses on what could of happened to it?

BFlinn181 09-19-2016 08:12 PM

:welcome:

I once drove a university fleet 15 passenger van that lost power 1400 miles from campus. Went to a garage and the catalytic converter was completely blocked. The honeycomb had broken into pieces that tumbled in the exhaust gases flow and had been turned into small nuggets of honeycomb. Perhaps yours did the same, reducing the size of the interior pieces until they got blown on down the exhaust pipe. In my case, the licensed mechanic took a 'lunch break' while I shook and rattled all the pieces out of the converter, then I reinstalled it and drove it until I got back to the campus garage.

You will obviously have to replace the converter, but I'd also check that the contents of the catalytic converter haven't blocked the muffler downstream from the converter.

2 Stroker 09-19-2016 11:00 PM

We have a 98 Honda Accord and the catalytic converter according to my scan tool needed to be replaced, every 100 or so miles I would turn off the light on the dash through the OBD2 port.
Now the believe it or not part. The wife seen a you tube on catalytic converter cleaning, they never ware out just get sick as long as you can see through the honeycombs the cat just needs to be cleaned and Honda wanted $1700 for a new one.:facepalm:
All I did was pull it off and get a bucket of water and 2 to 4 oz of laundry detergent (liquid) and suds it up. Left it in one day pulled and put the other end in for a day moving it up and down just like your washing clothes. On the third day pulled it and rinsed it with clean water, set in the sun all day to dry. Reinstalled and that was 2 years ago still no codes:thumb:

2 stroker

BFlinn181 09-19-2016 11:09 PM

Quote:

Originally Posted by 2 Stroker (Post 3261581)
We have a 98 Honda Accord and the catalytic converter according to my scan tool needed to be replaced, every 100 or so miles I would turn off the light on the dash through the OBD2 port.
Now the believe it or not part. The wife seen a you tube on catalytic converter cleaning, they never ware out just get sick as long as you can see through the honeycombs the cat just needs to be cleaned and Honda wanted $1700 for a new one.:facepalm:
All I did was pull it off and get a bucket of water and 2 to 4 oz of laundry detergent (liquid) and suds it up. Left it in one day pulled and put the other end in for a day moving it up and down just like your washing clothes. On the third day pulled it and rinsed it with clean water, set in the sun all day to dry. Reinstalled and that was 2 years ago still no codes:thumb:

2 stroker

Nice story and clever solution, but the OP's catalytic converter is empty of the honeycomb grids, all the soaking in the world won't restore the interior of the converter.

2 Stroker 09-20-2016 12:43 AM

Bob
You are right. I missed that part. My mind was somewhere else.
2 stroker

speed racer 09-20-2016 07:18 AM

Any thing hitting the cat. can crack the material inside and evetualy it will fall apart and be blown out by the exhaust. The problem is where did it go. It ends up in the muffler and restricts the flow so you have to remove the muffler and try to clean it out or replace it also.

JohnRR 09-20-2016 07:35 AM

Running without the cats will cause a distinct drop in low end power and fuel mileage, I found that out the hard way.

The fuel mileage problem may have been the fact it would continually down gear for the slightest hint of a uphill incline.

BFlinn181 09-20-2016 10:24 AM

Quote:

Originally Posted by JohnRR (Post 3261800)
Running without the cats will cause a distinct drop in low end power and fuel mileage, I found that out the hard way.

The fuel mileage problem may have been the fact it would continually down gear for the slightest hint of a uphill incline.

Since the catalytic converter only chemically changes the composition of the exhaust gases, I'm curious as how it "will cause a distinct drop in low end power and fuel mileage"? When the engine lost all power above idle speed and had no power, I knew the exhaust was blocked and discovered the converter had disintegrated and blocked exhaust flow. Removing the catalytic converter would increase exhaust gas flow, but I don't understand how it would cause the issue you report. Perhaps a sensor downstream of the converter changed the ECU's air/fuel mix or timing?

F4Gary 09-20-2016 10:38 AM

So is Kalifornia using a tailpipe sniffer or just the OBD port? Is there an O2 sensor after the cats?

Ford? Chevy? Try posting in your chassis forum.

As has been said, the contents of your cat are now clogging your muffler.

JohnRR 09-21-2016 08:52 AM

Quote:

Originally Posted by BFlinn181 (Post 3262033)
Since the catalytic converter only chemically changes the composition of the exhaust gases, I'm curious as how it "will cause a distinct drop in low end power and fuel mileage"? When the engine lost all power above idle speed and had no power, I knew the exhaust was blocked and discovered the converter had disintegrated and blocked exhaust flow. Removing the catalytic converter would increase exhaust gas flow, but I don't understand how it would cause the issue you report. Perhaps a sensor downstream of the converter changed the ECU's air/fuel mix or timing?

No idea to put forward what caused it only reporting the results, maybe less back pressure, maybe as you say a sensor. I forgot to mention it was way louder than stock especially driving next to the concrete barriers and accelerating from a stand still.

The noise and power loss went away as soon as the cats were reinstalled.

I put it in my mind as a loss of back pressure.

TQ60 09-21-2016 09:08 AM

There are two types of o2 sensor failure.

Just blow out which will cause a code and this is almost none of instances and the most common is "lazy" meaning it reads incorrect.

If we recall the output is somewhere around 1 volt or so.

What usually happens is they get lazy or the range slowly shifts but still can output that 1 volt but it is in a different place.

Think 65 mh instead of 55 ....

So the computer is happy but engine is running rich.

Over time more rich until the converter has more fuel than designed for and it fails.

Learned hard way...If cat fails change sensor too ad cat should last life of car so to speak.

Ford used those honeycomb ones that break so something wracking a hot one could have cracked it.

Here is another use for the ir thermometer.

Upon cold engine start monitor cat temp.

A blown out one stays cool.

Working one gets hot evenly and clogged one gets hot but exit pipe not so much.

OP sounds like replacement in order along with muffler.

Also note many sensors are generic bosch (spelling?) , you can use auto zone.com to get the part number and then amazon often has exact same unit for much less and it is oem for most as they made many of the "branded" parts.

jleamo1 09-21-2016 02:06 PM

Quote:

Originally Posted by JohnRR (Post 3263276)
No idea to put forward what caused it only reporting the results, maybe less back pressure, maybe as you say a sensor. I forgot to mention it was way louder than stock especially driving next to the concrete barriers and accelerating from a stand still.

The noise and power loss went away as soon as the cats were reinstalled.

I put it in my mind as a loss of back pressure.

Same happened to me with my V10 (last coach) I took it off thinking it would run better...wrong, lost bottom end torque, put it back on. I was shocked how much of a slug it was without it.

OP replace it and the muffler, you can purchase universal ones that might keep your cost down.

billsimi 09-21-2016 03:29 PM

Catalytic converters?
 
First off thanks to all of you!!!! This is the first time I have tried this way to get information.
Today I removed the muffler and it does rattle but I can't get anything to come out of ether end.
I have also done a little math/investigation with my poor excuse of a log book. From basically new I have averaged 7.39 mpg, sense May 2015 when the tire blew out I have only gotten 5.82 so I think I know the reason the catalytic converter is gone. I guess if I computed my gas mileage instead of just writing down the date,mileage, cost and gallons only I would have noticed a lot sooner something was amiss! I will now start to figure mileage each time, lesson learned!
I would like to know a little more about needing a new muffler, I must admit that because I have never needed to pushed this coach hard I didn't notice any lack of power.
THANKS AGAIN

JohnRR 09-21-2016 05:21 PM

My inlet pipe was a short distance from a flange once, it was taken apart at that flange it was easy to look down the pipe with a mirror and flash light and see the damaged honeycomb.


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