Rennlist

99 Failed AOS/Coolant leak?

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

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH99 Failed AOS/Coolant leak?

Reported or suspected cause

water pump

Suggestion or failed attempt

No successful repair reported for this finding.

0
Identified cause: 1
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 suspect 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.

Suspected cause
Thought it was the water pump.
Original post Read captured discussion
99 Failed AOS/Coolant leak?

Frequently discussed work

Test but

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
Sent her out to the garage to complete the DIY "Failed AOS" test but then she noticed coolant leaking near the rear of the engine, closer to the driver's side.
Original post Read captured discussion
99 Failed AOS/Coolant leak?

Read full discussion summary

Leading evidence: 'water pump' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, the most frequently mentioned possible cause is 'water pump' (1 discussions; 0 report identifying it and 1 suggest it). The most frequently discussed action is 'Test but' (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 · 2 captured posts examined · 0 partial discussions

Compare 1 other evidence results

Test but

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
Sent her out to the garage to complete the DIY "Failed AOS" test but then she noticed coolant leaking near the rear of the engine, closer to the driver's side.
Original post Read captured discussion
99 Failed AOS/Coolant leak?

Frequently discussed actions (1)

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

Test but

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
Sent her out to the garage to complete the DIY "Failed AOS" test but then she noticed coolant leaking near the rear of the engine, closer to the driver's side.
Original post Read captured discussion
99 Failed AOS/Coolant leak?

Reported and suspected causes (1)

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

water pump

No successful repair reported for this finding.

0
Identified cause: 1
Suspected cause: 0
Reported fixes

Read evidence and context

Discussions that suspect 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.

Suspected cause
Thought it was the water pump.
Original post Read captured discussion
99 Failed AOS/Coolant leak?

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.

2 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: 20261027T061840Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Wife said her 996 had a rough idle, saw some white smoke, accompanied by an odd noise. Drove 1 mile back home. Noise and rough idle went away. Still a little smoke. Parked car, shut down engine. Called me with her issue. Sent her out to the garage to complete the DIY "Failed AOS" test but then she noticed coolant leaking near the rear of the engine, closer to the driver's side. Coolant was raining down . I found a post that mentioned coolant runs through the AOS. Is this correct? Another post pointed to the coolant expansion tank, since leak looked liked it was on the left. Engine was off before she looked to see where smoke came from. I'm out of town, so I can't provide more detail. Any thoughts to help calm my nerves till I get home? Thanks PS Car was just in for the two CEL's that usually come on regarding a leak in the secondary air/evap system. They found a leak via a smoke test and fixed the line. Now 30 miles later, this happens.

POST 2Original post

Yes. A coolant leak can also be a part of AOS failure. Had the same problem. Thought it was the water pump. AOS should be Air-Oil-Coolant Separator.

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