3 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHA P1109, 0420 and 0430 tale
Reported or suspected cause
maf issue (i used
Suggestion or failed attempt
No successful repair reported for this finding.
0
Identified cause
1
Suspected cause
0
Reported fixes
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 suspect a cause
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.
Suspected cause · Original poster
I figured, ok, probably a MAF issue (I used to have a K&N Cold air intake on the car), so I cleaned the MAF.
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.
Unsuccessful attempt · Original poster
I figured, ok, probably a MAF issue (I used to have a K&N Cold air intake on the car), so I cleaned the MAF. Drove about 50 miles, and the codes came back.
Leading evidence: 'maf issue (i used' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'maf issue (i used' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Clean mass air flow sensor' (1 discussions). For that action, 0 discussions report a resolution and 1 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
If you look up some of my other threads, you'll see I had to have my heads rebuilt last summer - in the process, replaced a bunch of parts, seals, etc.
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
I remembered looking up DME reset info after I finished up the work, but left it at that.
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 report an unsuccessful attempt
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.
Unsuccessful attempt · Original poster
I figured, ok, probably a MAF issue (I used to have a K&N Cold air intake on the car), so I cleaned the MAF. Drove about 50 miles, and the codes came back.
These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.
Clean mass air flow sensor
No successful repair reported for this finding.
0
Reported fixes
1
Unsuccessful attempts
1
Discussions
Read evidence and context
Discussions that report an unsuccessful attempt
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.
Unsuccessful attempt · Original poster
I figured, ok, probably a MAF issue (I used to have a K&N Cold air intake on the car), so I cleaned the MAF. Drove about 50 miles, and the codes came back.
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
If you look up some of my other threads, you'll see I had to have my heads rebuilt last summer - in the process, replaced a bunch of parts, seals, etc.
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.
3 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 · 0 excluded by outcome qualification · 0 adjusted by outcome qualification.
0 acknowledgements have no verified action link; they do not establish a repair result.
Generation: 20261026T133652Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
Hopefully this thread will help document a successful resolution. We'll see!
If you look up some of my other threads, you'll see I had to have my heads rebuilt last summer - in the process, replaced a bunch of parts, seals, etc.
I also did a number of performance upgrades - IPD Competition Plenum, GT3 throttle body, 997 headers and put on a new Top Gear catted X-pipe. All work/mods were done about under 1000 miles ago.
Driving the car about a month ago, got a CEL. Drove home, hooked up the Durametric, and pulled a P1109, 0420 and 0430. I figured, ok, probably a MAF issue (I used to have a K&N Cold air intake on the car), so I cleaned the MAF. Drove about 50 miles, and the codes came back. Hmm. Okay, so maybe the MAF is bad? So I bought a new MAF. Put it on, this time drove it for about a week and probably about 200 miles... and the codes are back again!
Any ideas where to troubleshoot next? For reference, the GT3 throttle body I used was brand new, so I really hope the throttle body isn't the issue. I have to figure the 0420/0430 codes are resultant from the 1109 code... if not, I'll have to send a quick email to Topgear letting them know my new cats aren't functioning properly.
A few questions that might help.
1) Have you tried e-gas calibration?
2) What's your MAF voltage (read from Duramectric) when you turn the key to the last position before cranking?
3) What's your MAF voltage (and mass air flow in kg/hr) at idle with fully warmed up engine? (no load such as a/c)
4) At idle, fully warmed up (no load) on both banks, does the precat O2 sensor voltage swing between 0.2v to 0.7v about once a second? Does the postcat voltage stay more of less at ~0.7v?
5) What are the RKAT and FRA values on both banks?
I'm embarrassed to admit I forgot about the e-gas calibration. I remembered looking up DME reset info after I finished up the work, but left it at that. I'm going to give it a shot and see how it goes. I'll play around tomorrow and get the rest of the numbers too.
This is a source reference. Confirm exact model applicability in the original material.
