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Coolant in Oil

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHCoolant in Oil

Leading reported evidence

Check coolant tank cap

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
I would check the coolant tank cap.
Original post Read captured discussion
Coolant in Oil

Read full discussion summary

Leading evidence: 'Check coolant tank cap' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check coolant tank cap' (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 · 5 captured posts examined · 0 partial discussions

Compare 2 other evidence results

Replace with the newer (fixed) cap 996 106 447 01

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
If it has condensation or if the cap is part number 996 106 447 00 then it needs to be replaced with the newer (fixed) cap 996 106 447 01.
Original post Read captured discussion
Coolant in Oil

Test each cylinder will islolate

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
Preasure testing each cylinder will islolate which cylinder is the culprit.
Original post Read captured discussion
Coolant in Oil

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 coolant tank 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
I would check the coolant tank cap.
Original post Read captured discussion
Coolant in Oil

Replace with the newer (fixed) cap 996 106 447 01

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
If it has condensation or if the cap is part number 996 106 447 00 then it needs to be replaced with the newer (fixed) cap 996 106 447 01.
Original post Read captured discussion
Coolant in Oil

Test each cylinder will islolate

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
Preasure testing each cylinder will islolate which cylinder is the culprit.
Original post Read captured discussion
Coolant in Oil

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.

5 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: 20261026T083035Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

We just brought in to our shop a '99 C2 with only 30,000 miles and coolant in the oil. It looks like it may have the dreaded "Porous Block". Does anyone have a list of engine serial numbers reported to have this problem? I seem to remember someone compiling a list. I believe this happened with 98 & 99 Boxsters and 99 911's. With only 30k miles, I would expect that Porsche would help with the cost of replacement if that is necessary. Len Cummings BoxsterGT Lifetime Rennlister

POST 2Original post

I don't know that a list of engine serial numbers exists. I know there are folks trying to establish a pattern for rear main seal (RMS) oil leaks, but I haven't seen the "oil in coolant" problem on the Forums for quite a while.

POST 3Original post

in 28,800 miles over 10 months i've watched my coolant level go half way down in the reservoir in the engine compartment. i've never found a single drop of anything on the garage floor but on a few occassions smelled anti-freeze after a very hard drive. ideas?

POST 4Original post

Don't overlook the head gasket. That is more likely than a porous block, since there are sleeves between the cylinders. In extreme cases, there will be steam coming out of your exhaust, smelling like sweet anti-feeze. Preasure testing each cylinder will islolate which cylinder is the culprit. Good luck.

POST 5Original post

I would check the coolant tank cap. If it has condensation or if the cap is part number 996 106 447 00 then it needs to be replaced with the newer (fixed) cap 996 106 447 01. Almost all of the "00" caps leak.

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