4 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCHValve control issues, what do you guys think this may be?
Leading reported evidence
Replace coil and plug
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 · Original poster
Initially I did the simple thing, swapped coil and plug with cylinder #6.
Valve control issues, what do you guys think this may be?
Read full discussion summary
Leading evidence: 'Replace coil and plug' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check cam/crank correlation and i am <4 degrees' (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
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 · Original poster
I didn't mention it, but I replaced the MAF and all 4 O2 sensors when I did the engine rebuilt 15k miles ago.
Valve control issues, what do you guys think this may be?
Use durametric
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 · Original poster
By the way, I also used durametric to check cam/crank correlation and I am <4 degrees on both banks, so timing didn't skip.
Valve control issues, what do you guys think this may be?
Check cam/crank correlation and i am <4 degrees
Suggestion or failed attempt
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 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
By the way, I also used durametric to check cam/crank correlation and I am <4 degrees on both banks, so timing didn't skip.
Valve control issues, what do you guys think this may be?
Replace intake lifters
Suggestion or failed attempt
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 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
It looks to me that I am going back in and at least replacing intake lifters on one bank (if I am this far in I am also refreshing cylinder 1 & 2 intake lifters), but how do I tell if the cam phaser is good or not?
Valve control issues, what do you guys think this may be?
Replace intake lifters
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
It looks to me that I am going back in and at least replacing intake lifters on one bank (if I am this far in I am also refreshing cylinder 1 & 2 intake lifters), but how do I tell if the cam phaser is good or not?
Valve control issues, what do you guys think this may be?
Coverage and how to read this overview
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.
4 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: 20261026T213932Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
A little background. 2002 C4S with 90K on the clock and only 15k on the engine (I put in a Porsche reman shortblock and sent heads to machine shop ~15k miles ago). Recently I would get a misfire in cylinder 3, intermittently. I couldn't get the condition to repeat consistently, but the P0303 code would get stored after a few days of driving. Initially I did the simple thing, swapped coil and plug with cylinder #6. The same error came back on cylinder 3, so I know it is not a coil/plug issue. Then more recently I got more errors on a recent drive (p0300, p0303, P1371 and P1363). THe only difference that I can tell before now and previously is that this was on an unusually warm day, while the P0303 error was on days with temperature below freezing. Not sure if that matters, but I thought I would mention it. Seems like this is a valve control issue based on these codes. One thing that I don't understand is why the p0300 error came up. I understand that this is a multi-cylinder misfire code, and would make sense if I had a P0301 or p0302, etc., but I only have a specific misfire on cylinder 3. Now despite the block and heads being only 15k miles old, the valve control system (cam, lifters, phaser, solenoids) are still original from 2002 with 90k. Curious to get community input on what this issue may be. It looks to me that I am going back in and at least replacing intake lifters on one bank (if I am this far in I am also refreshing cylinder 1 & 2 intake lifters), but how do I tell if the cam phaser is good or not? Are cam phasers a known failure item by around 90k? Could this be solenoid driven? By the way, I also used durametric to check cam/crank correlation and I am <4 degrees on both banks, so timing didn't skip.
I didn't mention it, but I replaced the MAF and all 4 O2 sensors when I did the engine rebuilt 15k miles ago. Therefore I doubt that it is a MAF< and the symptoms being single cylinder misfire and timing codes again doesn't point at the MAF.
This is a source reference. Confirm exact model applicability in the original material.
