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911uk

Mayo like stuff in oil filler

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

Discussion summary

YOUR RESEARCHMayo like stuff in oil filler

Leading reported evidence

Run enough/hot enough

Suggestion or failed attempt

No successful repair reported for this finding.

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0
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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 contain suggestions
1

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Suggestion

the car isn't being run enough/hot enough to evaporate the water in the neck filler.

Mayo like stuff in oil filler
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Leading evidence: 'Run enough/hot enough' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run enough/hot enough' (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 · 9 captured posts examined · 0 partial discussions

Compare 2 other evidence results

Run sustained duration

Suggestion or failed attempt

No successful repair reported for this finding.

0
Reported fixes
0
Unsuccessful attempts
1
Discussions
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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 contain suggestions
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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

Effects most cars if you only drive for short journeys all the time, as the engine never fully heats up with a run for a sustained duration

Mayo like stuff in oil filler

Use lot of oil

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

The car also appears to be using a lot of oil.

Mayo like stuff in oil filler
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.

Run enough/hot enough

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

the car isn't being run enough/hot enough to evaporate the water in the neck filler.

Mayo like stuff in oil filler

Run sustained duration

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

Effects most cars if you only drive for short journeys all the time, as the engine never fully heats up with a run for a sustained duration

Mayo like stuff in oil filler

Use lot of oil

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

The car also appears to be using a lot of oil.

Mayo like stuff in oil filler
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.

9 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: 20261026T113718Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

I went to top up the oil in my car today (996 C4S). When I took off the filler cap, I noticed that the inside was covered in a thick, yellow substance like mayonnaise or custard. Should I be worried?? The car also appears to be using a lot of oil. Any suggestions? Thanks Neil. Migration info. Legacy thread was 11629

POST 2Original post

Sounds like your coolant is leaking into the engine casing and mixing with the water, hence the "Mayo". Early 996 blocks were prone to going porous, but I thought Porsche had erradicated the problem, better take it back to the OPC Migration info. Legacy thread was 11633

POST 3Original post

Neil. Yeah it sounds serious. If the car has sat for a while unused, or used for only short journeys it is possible it is just a bit of condensation in the engine, but it is more likey coolant in the oil, as Poon says. Definitely a trip to the OPC. Migration info. Legacy thread was 11634

POST 4 / ORIGINAL POSTEROriginal post

Guys, thanks for the feedback. Booked into OPC - I'll let you know the outcome. Neil Migration info. Legacy thread was 11773

POST 5Original post

Neil although it could as Poon suggests ( worst case) 996 are prone to producing this type of junk on the filler cap if you don't drive far enough and fast enough to burn of wter vapour. Migration info. Legacy thread was 11779

POST 6Original post

Old forum user Unidentified(11139) wrote: mine does this, i use it every day for very short journeys of around 4 miles. Everyone i've spoke to says the same thing, thats its bound to generate condensation as you're not getting the car warm enough to burn it off, plus the filler cap is so far away from the engine there's no way it can be a water/oil problem or it would appear on the dipstick. If you get custard streeks on the dipstick - be worried, in the filler tube - no worries just clean it out. Migration info. Legacy thread was 131834

POST 7Original post

Classic short journey syndrome ! Effects most cars if you only drive for short journeys all the time, as the engine never fully heats up with a run for a sustained duration Migration info. Legacy thread was 131883

POST 8Original post

As Admin says, mayo in the oil filler cap is a sign of moisture mixing with the residual oil in the neck of the cap... the car isn't being run enough/hot enough to evaporate the water in the neck filler. Migration info. Legacy thread was 131927

POST 9Original post

Beware what the OPC say.. They may want to cover themselves BUT I have heard both sides of the story.. Definately mine has 'small' amount of mayo when not used much .. It's emmulsification of water & oil.. Particularly this time of year when there's dew in the mornings a small ammount of moisture in the form of condensation is bound to lie in the filler pipe/cap. More importantant is to check if there's OIL globs in the Water.. On many cars this is sign of head gasket or pourosity. Also I think it's made more a problem with the filler cap lying flat.. The people with great experience in this are Autofarm http://www.autofarm.co.uk/engines/water_cooled Good luck and don't loose sleep until you know for sure if there's a problem. There's a lot of hype out there ! Migration info. Legacy thread was 132099

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