Community Forums

Fred and Bonnie · 08-05-2007, 11:08 AM

My good friend called and said he was broke down in Sequim, WA. The diagnoses was a clogged right side catalytic converter caused by a some what loose exhaust manifold/tail pipe connection. The ECM was receiving a false "lean" condition and was running the engine
"Rich". The "Rich" condition changed the converter properties causing the clog. No "Check Engine" light, no drop in performance and no drop in fuel mileage until the engine just quite. The left side tail pipe is loose and the shop suspects that converter is damaged.

The coach is a 2004 W22 on an '03 chassis with around 30k miles on the unit.

Anyone have thoughts on this?

Fred

Fred and Bonnie · 08-05-2007, 11:08 AM

My good friend called and said he was broke down in Sequim, WA. The diagnoses was a clogged right side catalytic converter caused by a some what loose exhaust manifold/tail pipe connection. The ECM was receiving a false "lean" condition and was running the engine
"Rich". The "Rich" condition changed the converter properties causing the clog. No "Check Engine" light, no drop in performance and no drop in fuel mileage until the engine just quite. The left side tail pipe is loose and the shop suspects that converter is damaged.

The coach is a 2004 W22 on an '03 chassis with around 30k miles on the unit.

Anyone have thoughts on this?

Fred

JimAerbus,W22,2003 · 08-05-2007, 01:17 PM

You know that whole thing sounds "Fishy" to me. The check engine light should have come on because that indicates trouble with the "Emissions" system..Instant clogged convertor with no other indications?? Convertors just don't clog instantly, and a loose manifold I would think would allow more air into the system not less. Is this guy saying that some kind of gasket or something got into the convertor and clogged it?? That whole deal doesn't sound right.. just my 2 cents. Jim

Fred and Bonnie · 08-05-2007, 02:45 PM

Jim, I don't believe any gasket material got into the convertor. The tech, a well respected WCC shop, stated the increase air into the tailpipe caused the sensors to pick-up a lean condition, therefore compensating to create the rich condition. I know, how could that much air get into the system and no exhaust noise be detected, nor the "Check Engine" light not come on.

If this would have happened in earlier times the first conclusion would have been leaded gas was used.

The shop went on to say this coach was not involved in the Catalytic Converter recall of years past.

I guess we may never find the real cause.

Fred

Full-Timers · 08-05-2007, 02:59 PM

Not sure about other states but, in California anything that has to do with smog like a Cat is covered for, I think, 5 years. That means FREE.

JimAerbus,W22,2003 · 08-05-2007, 03:19 PM

If they are a well respected Workhorse shop why are you asking us?? In your first post you don't mention that little fact. I thought they where stuck out in some Podunk shop or something...

Trek-Cyclist · 08-05-2007, 05:37 PM

If you look in the back of your WH manual it will list the "Federal" emission standard warranty It used to be by State but they are coverd under Federal Emission Standards some are 5 years some are 7 you should read it all.. WH tried to charge me for a Anti-knock sensor after the 3 year 36,000 miles but it was covered for 5 years which includes a lot of equipment... I think even spark plug wires... do your homework, they don't!
Good Luck

Fred and Bonnie · 08-05-2007, 06:01 PM

Guys, there is no question that it will be covered under the emissions warranty.

I would just like for someone to explain how this situation is possible.

I have never heard of a catalytic converter clogging under a "Rich" condition.

Fred

Trek-Cyclist · 08-05-2007, 06:24 PM

I understand,,,, No I never heard of it. Especially when no indacator lights came on.

I was just making sure that those that didn't know about the Heavy Duty Gas Engine coverage..
It's much different then the assumed 3 year 36,000 coverage that some believe...
Cats are 8 years/80,000.

Tenn.Vol. · 08-06-2007, 06:16 AM

About a yr. ago the Check engine light came on in the Liberty, pulled
out the SCAN GAGUE II, it showed code maybe 4420 or something ????
Called my MOchanic, he said 02 sensor in front of cat (has 4) need to
be changed in pairs. It COULD be telling the ECU that it was a
LEAN condition, ECU would richen up the fuel and over time would
take out the cat. Need to be changed sooner rather than later.
And under warrenty THEY would only change the bad 02 sensor.

So I change them both, I am thinking $50 each....TENN.

Oemtech · 08-06-2007, 06:42 AM

I don't think it "clogs" per si... But, it gets contaminated with fuel and can no longer convert the exhaust gases.

Ultra RV Products · 08-06-2007, 07:20 AM

We have seen under a rich condition,the converters get so hot the break apart inside.This material usually ends up in the muffler.

Fred and Bonnie · 08-06-2007, 09:41 AM

<BLOCKQUOTE class="ip-ubbcode-quote"><div class="ip-ubbcode-quote-title">quote:</div><div class="ip-ubbcode-quote-content">Originally posted by Brazels RV Performance:
We have seen under a rich condition,the converters get so hot the break apart inside.This material usually ends up in the muffler. </div></BLOCKQUOTE>

Mike, what you stated sounds like what happened. I talked with my friend earlier today; he said the first indication was a sound that he thought was his transmission coming apart. Sure sounds like the converter came apart and dumped into the muffler.

Thanks for the explanation.

Fred

JB Driver · 08-10-2007, 09:34 PM

Well folks I'm the friend with the catalytic converter issue. What I can tell you is that the RV tech in Sequim, Washington told me. Both donuts were leaking air causing a leak mixture situation to the ECM computer which told the engine to give a more rich mixture thus causing a super heating situation which shut down the engine when the catalytic conveter went bad. Never had any warning lights or any indication of any type of problem was going on before it happened.

I was towed to a Workhorse repair facility in Sequim, Washington. Initially, Workhorse said fix the right cataltytic converter only. Thankfully, I had to go to a rally and motel it. Barry Long, the regional service manager for Workhorse was there and I was able to personally plead my case to have both catalytic converters replaced. After getting more information from the repair facility he authorizied that both catalytic converters to be replaced.

The whole incident was a very valuable learning experience. 1) Thankfully, I live in California and the state standard for catalytic converters requires a 70,000 mile or seven year warranty period on them. 2) Check the donuts where the headers and exhaust pipes come together on a regular basis. 3) I'm thankfully for the attention I received from Barry Long of Workhorse regarding this situation. Yes, the whole matter was covered under warranty.