Rennlist

Losing Coolant

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCHLosing Coolant

Leading reported evidence

Replace coolant tank a couple years ago

Performed · outcome unconfirmed

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 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 have replaced the coolant tank a couple years ago.
Original post Read captured discussion
Losing Coolant

Frequently discussed work

Replace air oil separator

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
Has anyone had the experience of the hose just leaking or am I looking at replacing the AOS?
Original post Read captured discussion
Losing Coolant

Suggestion
If you are going that deep in there to fix either one of those lines, replace the AOS.
Original post Read captured discussion
Losing Coolant

Read full discussion summary

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

Compare 3 other evidence results

Replace air oil separator

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
Has anyone had the experience of the hose just leaking or am I looking at replacing the AOS?
Original post Read captured discussion
Losing Coolant

Suggestion
If you are going that deep in there to fix either one of those lines, replace the AOS.
Original post Read captured discussion
Losing Coolant

Replace aos, and maybe even the coolant reservoir tank just

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
Replace the AOS, and maybe even the coolant reservoir tank just to be sure.
Original post Read captured discussion
Losing Coolant

Replace aos, there are many threads

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
Do a search on replacing AOS, there are many threads on that subject.
Original post Read captured discussion
Losing Coolant

Frequently discussed actions (4)

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

Replace air oil separator

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
Has anyone had the experience of the hose just leaking or am I looking at replacing the AOS?
Original post Read captured discussion
Losing Coolant

Suggestion
If you are going that deep in there to fix either one of those lines, replace the AOS.
Original post Read captured discussion
Losing Coolant

Replace aos, and maybe even the coolant reservoir tank just

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
Replace the AOS, and maybe even the coolant reservoir tank just to be sure.
Original post Read captured discussion
Losing Coolant

Replace aos, there are many threads

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
Do a search on replacing AOS, there are many threads on that subject.
Original post Read captured discussion
Losing Coolant

Replace coolant tank a couple years ago

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 have replaced the coolant tank a couple years ago.
Original post Read captured discussion
Losing Coolant

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: 20261027T154520Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

My '03 996 is losing coolant. It appears to be coming from a small hose attached to the AOS. see picture. The AOS appears to be difficult to get at and change. Has anyone had the experience of the hose just leaking or am I looking at replacing the AOS?

POST 2Original post

There are two coolant lines to the AOS, one is supply and one is return. If you are going that deep in there to fix either one of those lines, replace the AOS. It could be the AOS that is leaking. Mine did. Do a search on replacing AOS, there are many threads on that subject. It is a very difficult and frustrating job.

POST 3Original post

Agree with Joe. If it were my car, I�d be doing a UAOS replacement.

POST 4Original post

Do not neglect your cooling system, these cars are very prone to cracked heads from overheating due to coolant loss. Then you're in deep do do. Ask me how I know. Replace the AOS, and maybe even the coolant reservoir tank just to be sure. The job may be difficult but it is doable and you can find tips to make it easier, such as lowering the engine, on this web-site. Best of luck.

POST 5 / ORIGINAL POSTEROriginal post

Thanks for the comments. I have replaced the coolant tank a couple years ago. I will order the UAOS.

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