OBDII 'P0430' code. What caused it?
#1
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OBDII 'P0430' code. What caused it?
P0430 is Catalyst system efficiency below threshold (Bank2). A friend of mine told me it was the post-cat o2 sensor that caused the code. He said the output of the post-cat o2 sensor should not fluctuate too much if the cat is good. If the cat is bad, the post-cat sensor would fluctuate a lot and sets off the code. And he concluded that the bank2 cat is malfunctioning.
Anyone could confirm that and help?
P.S.Since my 993tt has two cats, I compared the outputs of the two post-cat o2 sensors but they fluctuated pretty much the same. And what I think that means is if bank2 cat is bad, bank1 cat should be bad as well and should have set off another OBDII code.
Anyone could confirm that and help?
P.S.Since my 993tt has two cats, I compared the outputs of the two post-cat o2 sensors but they fluctuated pretty much the same. And what I think that means is if bank2 cat is bad, bank1 cat should be bad as well and should have set off another OBDII code.
#2
I just looked it up in the OBD II Manual Supplement.
P0430 - TWC Conversion too loo (cylinders 4-6)
It determines the error by comparing the oxygen sensor amplitudes before and after the TWC.
The diagnosis procedure only has two steps:
1) Look for other DTC's, correct them, and erase the DTC.
2) If DTC P0430 comes back, replace the three way catalytic converter.
Hope this helps....
P0430 - TWC Conversion too loo (cylinders 4-6)
It determines the error by comparing the oxygen sensor amplitudes before and after the TWC.
The diagnosis procedure only has two steps:
1) Look for other DTC's, correct them, and erase the DTC.
2) If DTC P0430 comes back, replace the three way catalytic converter.
Hope this helps....
#4
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Don't focus on the most expensive fix first. Could be something as simple as an intermittent misfire causing slightly too much hydrocarbon entering the cat. If you haven't changed your rotors and cap in the last two or three years or cleaned the idle stabilization vale or even changed you oil in a while I would do so and clear the code. It might not come back. The cats on a 911 seem to be very robust. My last 911 I ran up to 150K miles and the cat was still going strong.
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Don't focus on the most expensive fix first. Could be something as simple as an intermittent misfire causing slightly too much hydrocarbon entering the cat. If you haven't changed your rotors and cap in the last two or three years or cleaned the idle stabilization vale or even changed you oil in a while I would do so and clear the code. It might not come back. The cats on a 911 seem to be very robust. My last 911 I ran up to 150K miles and the cat was still going strong.
#6
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Could be, but not my first guess because a bad sensor throws a slow code when they are dirty or a no signal code when they are bad.
#7
Instructor
Maybe even look up mode 6 data to see how close to failing the other cat may be.... Even look to see how bad the failed cat really is.
Curt
I doubt the O2 is failing. You are on the right track by comparing B1S1 with B1S2 data. If the wave forms are duplicate overlays with engine warm a 1500 to 2000 RPM or so your cat is toast.... Why the cat failed is still undetermined...
How close to failing the monitor test these "sport" cats are when new I have no idea...
Curt
I doubt the O2 is failing. You are on the right track by comparing B1S1 with B1S2 data. If the wave forms are duplicate overlays with engine warm a 1500 to 2000 RPM or so your cat is toast.... Why the cat failed is still undetermined...
How close to failing the monitor test these "sport" cats are when new I have no idea...