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YOUR RESEARCHWhat to do when the Fault codes reads "Catalytic Converter"
Leading reported evidence
Clean maf cleared the codes and the car
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Performed · outcome unconfirmed
I cleaned the MAF cleared the codes and the car ran perfectly, again I put the scope on the MAF just to be safe.
What to do when the Fault codes reads "Catalytic Converter"
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Leading evidence: 'Clean maf cleared the codes and the car' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'pre cat due' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Check coil packs and spark plugs' (1 discussions). For that action, 0 discussions report a resolution and 0 report an unsuccessful attempt. No action has an explicit, attributable resolution report under the current rules. These are forum reports and suggestions, not a confirmed diagnosis.
Source reports, not a diagnosis or a success probability. Counts refer to discussions and can overlap.
Explicit resolution reports before identified causes, performed actions and suggestions. Within each level, matching component labels precede direct query mentions and inherited thread context; successful versus unsuccessful discussion counts, owner confirmations and independent discussion support determine order. This is not a probability of success.
Discussions that performed work without a confirmed outcome
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Performed · outcome unconfirmed
I cleaned the MAF cleared the codes and the car ran perfectly, again I put the scope on the MAF just to be safe.
What to do when the Fault codes reads "Catalytic Converter"
Use 1st, up
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Roughly up to 20mph I use 1st, up to 30mph I use second, up to 40mph I use 3rd, and so on.
What to do when the Fault codes reads "Catalytic Converter"
Use 3rd, and so
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Roughly up to 20mph I use 1st, up to 30mph I use second, up to 40mph I use 3rd, and so on.
What to do when the Fault codes reads "Catalytic Converter"
Use oem
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What to do when the Fault codes reads "Catalytic Converter"
Reported and suspected causes (1)
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pre cat due
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Suspected cause
I figured my problem was pre cat due to the misfire since the misfire would be responsible for the 02 sensors going off, but I put the oscilloscope on them just to confirm that wasnt the problem.
What to do when the Fault codes reads "Catalytic Converter"
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22 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
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Outcome without a verified action link
I will post the final results when the issue has been resolved.
Depends upon the codes are. Could be aging O2 sensors.
Assuming it is not, and it is not in my car's case, what I've done with a P0430 error code in my Boxster is to move to and always use a top tier gas (when gas prices got real high I'd switch to discount brand but the error code would appear more often).
I also treated the engine to a bottle or two of Techron using it according to directions. I've done this just once though in the last oh 4 or 5 years.
The engine is kept in reasonably good tune, with plugs that do not have too many miles on them. Whatever their change schedule is or close to it.
I started driving the car a bit more aggressively. Nothing gruesome I just rev'd the engine out a bit more and modified my gear selection to select a gear to keep the rpms up a bit, mainly to keep them above 2K and preferrably above 2.5k. Roughly up to 20mph I use 1st, up to 30mph I use second, up to 40mph I use 3rd, and so on. Whatever keeps the revs up some. Short runs on the freeway I cruise at the limit in 4th instead of 5th, though on longer drives I'll use 5th.
I've managed to nurse a converter now for several years.
However, with cold weather here the CEL came on the other day and it was P0430. The code is always more likely to appear in colder temps.
If the above doesn't help or you do not want to bother you can consider what I"m considering and that is seeking out a used exhaust manifold/converter from one of the Porsche wreckers (Parts Heaven is just a few blocks away from my office) and then having the Porsche dealer tech replace the bad one.
I'll probably have him do this when I take the car in to have a leaking camshaft cover on that side addressed. Figure I'll save a bit of labor in the process.
Sincerely,
Macster.
^^^^ Why do you always write there long winded replies?
Post a few questions to the OP and when they reply with some answers, then write the diagnosis. Sometimes less is more.
OP please post the trouble code.
Don't spend $2000 at the dealer when you can get both factory cats for $2460 from Sonnen Porsche.
http://sonnenporscheoemparts.com/par...HAUST%20SYSTEM
If its a not a California car (but it looks like you are), the Catco OEM replacement converters are much, much cheaper. If you live in Commie California, drive across border and install in Az. or have a friend buy them for you. If your sure its the cats and not a sensor(s), maybe remove the exhaust and physically inspect? I think all aftermarket cats are stainless steel now and have 5yr/50K warranty.
Thanks to everyone for the ideas and suggestions. I am taking the car in Saturday for diagnosis, since the initial code which I posted here was one of the less expensive hand held units.
Macster
, I appreciate you suggestions, and most of them are already a part of my normal routine
I've had a couple of PMs with some unique suggestions and ideas which I will also consider. I will post the final results when the issue has been resolved. Thanks to everyone
If you have to replace your cats why not go with 200 cell high flow cats? I few of us run them and they will improve the cars exhaust sound and give you some added power. My xpipe sounds incredible with PSE.
GT3 like...
Hi, if your cats need to be replaced you should consider the Cargraphic Cats that are for sale ($1100)
at Road Sport Supply/ Stuttgart Performance in Orange County! I recently purchased these cats
for my 996.
rss.prmware.com
Yes. These are arise from the converters performing below par.
The reference I have if there are aging O2 sensor codes along with either or both codes is to replace the sensors indicated by the sensor related error codes and clear the codes and drive the car.
If the P0420/0430 error codes come back replace the converters.
The converters are basically unable to store oxygen and release it to process exhaust gases.
Contamination (leaded gasoline) or some fuel or oil additives can damage these.
They can just wear out.
Yet another failure mode is a mechanical failure the metal/ceramic matrix comes loose and exhaust flow through the converter is compromised. The converters need to be hot to work and they remain hot by working. If exhaust flow is wrong they cool down and their efficiency drops off pretty quick.
A bit strange both sides fail. Sometimes a coincidence is just that but is there anything that has been done to the engine or the exhaust system or possibly happened that could be a common failure point?
FYI if car is under 8 years old from original sale date they are covered under warranty as per EPA. I Porsche replace both my cats free of charge on my 2004 6 months ago.
that said if out of warranty I would opt to get sport cats and call it a day or try and find someone that upgraded and maybe has original cats for sale. However, with 2nd option you run risk of the used replacements going bad at a later date. So, if me i would deffinately go sport cats 200 cel.
Since you're in the People's Democratic Republic of California like me, remember that non-CARB-certified cats are grounds for failing the visual inspection... even if you pass the sniffer, catalytic converters that do not have the correct markings (I do not remember the proper CARB nomenclature for the ID number) are not allowed.
Now, in reality, no inspector is likely to search your catalytic coverter for the CARB number, but it's something you might want to be aware of. It would suck to pay out for high-flow cats and still fail smog.
Do you have a obd reader or durametric ?
If yes, I would recommend that you plot the values from the O2 sensors (all 4 of them).
What you should be seeing, after warmup, is that the reading are in an oscilating form or wave form.
If not, then one of the sensors is shot. I find it hard to believe that you are getting both CATS bad at the same time.
Hope that makes sense.
Uber has a good point as well.
If your mechanic can read the O2s then he should be able to read the MAF which will be in gms/sec I think.
If I remember correctly you should be getting a minimum of about 4.25 to 5.25 steady at idle.
As others have said, do a little diagnosing first. Test the functionality of your O2 sensors first, make sure they are functioning properly because it is the O2 sensors that will cause cat inefficiency codes. If both front and rear O2 sensors are functioning properly I would check Coil Packs and spark plugs. You don't necessarily need a misfire, just inefficient spark to not properly burn fuel and cause you to throw cat efficiency codes as well. It could also be the MAF as others have said, reading incorrect values can cause slight misfires due to incorrect fuel trim and burning very rich.
I got a cat efficiency code, multiple misfires, misfire on cylinder 1 and misfire on cylinder 5. I figured my problem was pre cat due to the misfire since the misfire would be responsible for the 02 sensors going off, but I put the oscilloscope on them just to confirm that wasnt the problem. They tested fine but could be better so I replaced them. I then moved onto the spark plugs, I was getting spark on every plug, but 1 and 5 were fouled a little and the plastic casing on the coil packs was cracking. I figured that this would only become a problem in the future so replaced them anyways. I them moved onto the MAF. I was running a K&N intake and found that the oil from the filter was clogging the MAF causing the misfire and O2 sensors to go crazy. I cleaned the MAF cleared the codes and the car ran perfectly, again I put the scope on the MAF just to be safe. It wasn't running quite as well as brand new so replaced it again as a precaution.
I ended up doing O2 sensors, Plugs, Coil Packs, and MAF which was still less than doing the cats which would have solved nothing . Even at that I could have just gotten away with cleaning my MAF
