Pelican Parts

Diagnosing OBDII code, could use some help 2003 C4S

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4 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHDiagnosing OBDII code, could use some help 2003 C4S

Leading reported evidence

Run fuel tank

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
I failed to mention though that I had run the fuel tank to within 40 miles of being empty.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Frequently discussed work

Check plugs and will

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
I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Read full discussion summary

Leading evidence: 'Run fuel tank' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check plugs and will' (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.

Read captured replies

1 matching discussions · 4 captured posts examined · 0 partial discussions

Compare 2 other evidence results

Check plugs and will

Suggestion or failed attempt

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
I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Inspect ignition coils

Suggestion or failed attempt

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
I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Frequently discussed actions (3)

These are separate views of the same evidence. Frequency alone does not establish a fix, and these counts must not be added together.

Check plugs and will

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
I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Inspect ignition coils

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
I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

Run fuel tank

No successful repair reported for this finding.

0
Reported fixes: 0
Unsuccessful attempts: 1
Discussions

Read evidence and context

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 failed to mention though that I had run the fuel tank to within 40 miles of being empty.
Original post Read captured discussion
Diagnosing OBDII code, could use some help 2003 C4S

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.

Pelican Parts: 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: 20261026T130754Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Car has been running well up to today. Got in the car started it and the CEL came on. The car misfires under load but free revs without issue although I am detecting a slight misfire when at idle. Checked to see what codes were thrown and got four. P0300(multi cyl misfire), P301(cyl 1 misfire), P0303(cyl 3 misfire), P0305(cyl 5 misfire). Sounds like whatever controls cylinders 1, 3, and 5 is not happy. Any thoughts or suggestions? Don't have the Bentley service manual yet, but I guess its in my immediate future.

POST 2 / ORIGINAL POSTEROriginal post

Well, I might chalk this one up to a wet engine. What I didn't mention in my first post was that I had just picked it up from Esoteric Detailers after having a Suntek clear wrap applied to the front clip. I also had the complete car detailed and clear sealed. I suspect that the coil packs got wet (during the prep) because after I cleared the codes the car runs as it should. Drove it to work this morning (40 miles) without issue. I've been told that the drivers side of the engine in particular is susceptible to misfires if the coil packs get soaked. I'll update this post as necessary if things change. Warren

POST 3Original post

These sorts of problems are usually due to the coil packs having cracks in their housings. Normally, the car should be able to drive in torrential downpour conditions where the rear tires will drench the engine. Might be worth a look before the rainy season begins.

POST 4 / ORIGINAL POSTEROriginal post

Quotes source post: 9195055

I failed to mention though that I had run the fuel tank to within 40 miles of being empty. After filling the tank and clearing the code i haven't had an issue. I'm thinking I picked up some garbage in the bottom of the tank causing the misfire. I'm coming up on 75K and so I will be checking the plugs and will inspect the coil packs. Thanks, Warren

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