5 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 Fault Code P0430
Leading reported evidence
Replace engines
Performed · outcome unconfirmed
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
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
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Performed · outcome unconfirmed
Prior to this issue, I had a coolant leak into Cylinder 1, and swapped engines.
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
Does P0430 specifically indicatate that my Cat is bad or are there other things I need to look at before spending the time and money to replace the cat or the 02 sensors?
Leading evidence: 'Replace engines' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Replace cat or the 02 sensors' (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 contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
Does P0430 specifically indicatate that my Cat is bad or are there other things I need to look at before spending the time and money to replace the cat or the 02 sensors?
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Replace cat or the 02 sensors
No successful repair reported for this finding.
0
Reported fixes
0
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that contain suggestions
1
0 original-poster resolution reports. Counts can overlap; they are not unique people or a success rate.
0 discussions have direct query context; 0 report a fix in that context. Other evidence may inherit the discussion’s subject.
Suggestion · Original poster
Does P0430 specifically indicatate that my Cat is bad or are there other things I need to look at before spending the time and money to replace the cat or the 02 sensors?
Counts describe captured discussions, not unique people or a diagnosis. Author identities are not reliably stored. Exact duplicate evidence is counted once across matching discussions; one discussion counts at most once per action/state. Multiple repairs reported together remain a combination. Suggestions and failed attempts do not establish a fix. Matches cover whole discussions and can include related faults, model variants and incomplete threads.
5 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.
Rennlist: 1 discussions
0 evidence records excluded for query context · 1 excluded by outcome qualification · 0 adjusted by outcome qualification.
1 acknowledgements have no verified action link; they do not establish a repair result.
Outcome without a verified action link
Try a couple of bottles of Techron and some expensive gas - did the trick on mine for a while until I got around to having the exhaust system replaced
I have a 2001 996 Carrera Cabriolet with 61K on it. I just started getting the fault code of P0430 "Catalyst System Efficiency Below Threshold Bank 2" When I bought the car last year all four 02 sensors were replaced so I'm bit skeptical whether this could be the problem but then again anything is possible. What is the probability that any of the o2 sensors would go bad after 16 months? I've heard that normally catalytic converters do not go bad but then again some have. I've reset the check engine light several times and the light comes back on intimately after 20 to 50 miles of driving. Does P0430 specifically indicatate that my Cat is bad or are there other things I need to look at before spending the time and money to replace the cat or the 02 sensors?
Catalytic converters definitely can go bad on these cars. The OEM ones cost an arm and a leg. Two years ago, I replaced my failing OEM cats (was getting P0420 and P0430, both banks) that had ~90K miles on them with a pair of OEM takeoffs from a parts car that had <70K miles on it. I did not replace the O2 sensors, and it cleared up my codes. I now have 112K on the car, and still haven't gotten those codes again. I figure I bought myself some time to coordinate a refresh of my now 'extra' cats with someone like Gert at Carnewal. (though I've dragged my feet on actually send the extra ones out to him for refresh)
I'm in the same boat. My mechanic says it's not a big deal, but it still bothers me when that check engine light pops up. I can't ignore it because I want to make sure the light isn't coming on for something else, unrelated. I passed emissions inspection right before it started, so I have a couple years before I have to find a fix for it. I did get an 02 Sensor code one time, but it has not come on again, so i'm unsure if this is related to my O2 sensor, or if it truly is the Cats. Prior to this issue, I had a coolant leak into Cylinder 1, and swapped engines. I'm thinking that Coolant got into the Cats and is what is causing the issue to pop up immediately after the engine was swapped.
The early 996 sometimes have cat elements that break loose .
This triggers fault code 420 or 430 .
Knock on the housing (like you would bang on a door) .
If the element is loose, you should hear the element moving inside.
This is what's left over of the elements, after some time :
This is a source reference. Confirm exact model applicability in the original material.
