morganabowen

Well, the car has been running great and with summer coming began looking into a paint job Then, yesterday the demon "check engine" light comes on I take the car to my mechanic and he puts it on the thingy and up pops these two codes. Catalytic Converter Called parts and the cost is $2000 Do I have any alternatives/choices

Capt. Obvious

Used ones off ebay/Craigslist or high-flow versions from Fabspeed are good (less expensive) options.

KrazyK

You must be mistaken sir, these cars are cheap to maintain.


But seriously, are cats breaking apart, failing from oil contamination, what? There are many aftermarket alternantives.

P.S. buy a code reader/clearer.

LordVicious

Hang on there cowboy, cats fail for a reason! First, clear the codes. You can pretty much drive on failed cats, well, forever ... depending on how they failed. If the exhaust pressure is anywhere near nominal your good to go. The most common way of killing your converters is running raw gasoline thru the exhaust. Do you recall anything weird happening with your fuel management (plugs, evaporator, tank overfilled, that-sort-of-thing)? That needs to be fixed or you will just kill another set of cats. Next up, O2 sensors (I would have said check for physical damage, but it's on both sides so prolly not.) I would assume for $2k your mechanic is doing all of this and more. I would hope much more.

soverystout

OEM cats from Sonnen Porsche are $1314.65 each. Which cat is bad? Both?

http://sonnenporscheoemparts.com/par...HAUST%20SYSTEM

morganabowen

He gave me a quote just for the cats is $2K. Since two codes popped up, P0430 and P0420, both are bad I'm gonna check around ebay and also Fabspeed. Thanks

Ubermensch

It seems unlikely for both cats to go bad at the same time. When I get codes pointing to both sides of the engine I tend to look up stream for the problem. Take a look at the voltage traces from the oxygen sensors (before and after) the cats to see what's going on. Ideally the sensors before the cats are sinusoidal and the readings after the cats are pretty flat. If you see no voltage you could just have a bad sensor. If you see sinusoidal waves after the cats that are off set from the upstream sensors it suggests bad cats. I chased a problem like this on a 4runner one time. I changed both sensors and was just about to change the cat when i realized a bad MAF would cause both sides to appear off at the same time. I cleaned the MAF and never had another code...

Macster

The factory guidelines state that if either or both of the above codes are accompanied by O2 sensor codes to replace the sensors indicated, clear the error codes, then road test the car.

If the converter error codes come on again replace the converters.

I've been dealing with an intermittent P0430 for years now in my 02 Boxster. I found switching to a top tier gasoline (mostly Shell but Chevron other brands work too) help keep the CEL dark.

dgmark

Gotta agree with Uber two bad cats at the same time would be odd without a drivability problem, unless you have been driving with the MIL lamp on for 6 months. Just because you have a cat efficiency code does not automatically point to the cats. If the cats are bad the O2 sensor wave forms on O2's after the cats will mimic the ones before the cats.
A cat that is up to temperature has very little oxygen coming out of it, therefor the sensor pattern will be relatively flat compared to the one in front of the cat. I suspect that something else triggered it. You also need to know what the short and long term fuel trims are, if they are normal clear the codes and drive it until it reruns the monitor. If no code reappears you are good to go.

kpl

I had a P0420 a month ago. Swapped the rear O2 sensors side to side to figure out if it was a bad cat or sensor and I haven't had a check engine light since...maybe had a bad connection or bad gas I'd guess.

morganabowen

I'm taking the car into the mechanic on Tuesday to follow through on some of the suggestions on this board. I will post the final results. Thanks everybody RL'ers are the best

halik

Ha the same cat code pop up on me (both at the same time) last week; I find the premise that both cat converters failed at the same time suspect at best. I've reset them and waiting to see if they come back, odds are there was somethign in the gas.

kpl

I got the P0420 again, so I need a new bank 1 cat. It took several hundred miles for the check engine light to come back on. Anyone got a low mileage one sitting around?

Macster

If you can't find one someone's taken off his car check out Parts Heaven in Hayward CA. 510 area code.

morganabowen

Isn't there a law here in California prohibiting the sale of used CC I called a local Porsche parts recycler and that is what they told me. This is so frustrating