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911uk

Missfire!

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4 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHMissfire!

Reported or suspected cause

aging alternator

Reported cause

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
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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 identifying 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.

Reported cause

I had suspiciously similar symptoms to yourself, which proved to be an aging alternator.

Missfire!
Frequently discussed work

Check charge rate at tickover

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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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

When the battery went I had the breakdown chap put a voltmeter on the battery terminals to check the charge rate at tickover.

Missfire!
Read full discussion summary

Leading evidence: 'aging alternator' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'aging alternator' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Check charge rate at tickover' (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.

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

Compare 4 other evidence results

corroded fuses - an instant fix (with much

Reported cause

No successful repair reported for this finding.

1
Identified cause
0
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 report identifying 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.

Reported cause

THE ONLY PROBLEM WAS CORRODED FUSES - an instant fix (with much

Missfire!

Check charge rate at tickover

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

When the battery went I had the breakdown chap put a voltmeter on the battery terminals to check the charge rate at tickover.

Missfire!

Clean around the terminals

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

Stevo's certainly right to suggest replacement fuses and a clean around the terminals.

Missfire!

Clean fuses (i assume

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

I'll try cleaning the fuses (I assume that you mean the ones in the engine bay Stevo?) and let you know what happens...

Missfire!
Frequently discussed actions (10)

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

Check charge rate at tickover

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

When the battery went I had the breakdown chap put a voltmeter on the battery terminals to check the charge rate at tickover.

Missfire!

Clean around the terminals

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

Stevo's certainly right to suggest replacement fuses and a clean around the terminals.

Missfire!

Clean fuses (i assume

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'll try cleaning the fuses (I assume that you mean the ones in the engine bay Stevo?) and let you know what happens...

Missfire!

Clean ht leads and the distributor cap

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

In the mean time I have tried cleaning all the HT leads and the distributor cap with a healthy coating of WD40 but this made no real difference (although it did start very easily).

Missfire!

Clean terminal connections into

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

improved smoothness and performance) was to replace the fuses and to clean the terminal connections into which they fit!

Missfire!

Replace battery apeared

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

Replacing the battery apeared to cure the problem and for another 2 weeks all was well in porsche land.

Missfire!

Replace fuses

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

improved smoothness and performance) was to replace the fuses and to clean the terminal connections into which they fit!

Missfire!

Run )

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

This may explain why the battery discharged (it wasn't being refreshed during a run).

Missfire!

Run very rough indeed

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

However, today on my drive to work (approx 23miles on duel carriageways) it began to run very rough indeed.

Missfire!

Use engine management systems

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

"All the cars covered by this manual use engine management systems

Missfire!
Reported and suspected causes (2)

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

aging alternator

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that report identifying 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.

Reported cause

I had suspiciously similar symptoms to yourself, which proved to be an aging alternator.

Missfire!

corroded fuses - an instant fix (with much

No successful repair reported for this finding.

1
Identified cause
0
Suspected cause
0
Reported fixes
Read evidence and context
Discussions that report identifying 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.

Reported cause

THE ONLY PROBLEM WAS CORRODED FUSES - an instant fix (with much

Missfire!
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.

  • 911uk: 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: 20261027T082735Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Hi all, For the past three months my new 3.2 has behaved perfectly. However in the past two weeks it has developed a few problems. The first I put down to a dead battery (lumpy running and having to jump start the car every morning were the reasonably obvious simptoms). Replacing the battery apeared to cure the problem and for another 2 weeks all was well in porsche land. However, today on my drive to work (approx 23miles on duel carriageways) it began to run very rough indeed. Any ideas? or am I going to have to run it upto Autofarm for a proper look see? Migration info. Legacy thread was 18138

POST 2Original post

This is from a email I sent to the PCGB but they didnt publish. There is a new manual (which I purchased after fixing the problem!) for the 911 Carrera printed by Bentley Publishers which contains this paragraph regarding the electronic ignition on the 911. Page 200-13 Engine management "All the cars covered by this manual use engine management systems that rely on precise electrical signals for proper operation. Some of the DME circuits operate on very low current and are sensitive to increased resistance due to faulty or corroded wiring or connectors. If any of these signals are distorted, incorrect or missing the car can develop major driveability problems." Several months ago the car started to fire on 3 or 4 or 5 cylinders when started from cold - then it would pick up on the offending cylinders when the engine was warm.(see email below) THE ONLY PROBLEM WAS CORRODED FUSES - an instant fix (with much improved smoothness and performance) was to replace the fuses and to clean the terminal connections into which they fit! There appears to be a steady trickle of problems on the problem pages of the magazines and web chat room sites all of which are contributed to by corroded fuses. Ray Northway hit the nail on the head when he said he had seen this with earlier cars but not the 3.2 - but the reason its happening now is that the cars continue to age! The car also reponded very well to a new distributer rotor arm and a clean up of the distributer cap terminals. Migration info. Legacy thread was 18142

POST 3Original post

Tim, Stevo's certainly right to suggest replacement fuses and a clean around the terminals. Rotor arm renewal and clean up of dist cap is only a few quid too. I had suspiciously similar symptoms to yourself, which proved to be an aging alternator. This may explain why the battery discharged (it wasn't being refreshed during a run). If the alternator is not producing enough juice, or what it is producing is being lost by poor connections/earth straps/fuse holders etc, this will cause the ecu to malfunction and incorrect electrical signals being sent to injectors etc. This will make for a very lumpy ride indeed. You need an electronic charge tester to compare current at back fuse box with battery at idle, and same again with engine under moderate load. Good luck. Migration info. Legacy thread was 18148

POST 4 / ORIGINAL POSTEROriginal post

Adam, When the battery went I had the breakdown chap put a voltmeter on the battery terminals to check the charge rate at tickover. It was bang on spec at 14.5V. I guess I could get a meter from work and test at load but I suspect that the altenator is OK. I'll try cleaning the fuses (I assume that you mean the ones in the engine bay Stevo?) and let you know what happens... In the mean time I have tried cleaning all the HT leads and the distributor cap with a healthy coating of WD40 but this made no real difference (although it did start very easily). Migration info. Legacy thread was 18149

This is a source reference. Confirm exact model applicability in the original material.