Planet-9

987.2 Loud startup, then quiet

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3 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis

THIS DISCUSSION / SOURCE-DERIVED OVERVIEW

Discussion summary

YOUR RESEARCH987.2 Loud startup, then quiet

Reported or suspected cause

valves opening up

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
cars is caused by the valves opening up on cold start and then closing when it goes quiet, but this is incorrect.
Original post Read captured discussion
987.2 Loud startup, then quiet

Frequently discussed work

Adjust over

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
There is a simple mod that many have done where the clamps on the crossover pipes behind the "T" for the tips are bolted on are loosened and then adjust over to one side, and then you can tune the loudness to your liking by adjusting how much the clamps cover the open slot between the two muffler sides.
Original post Read captured discussion
987.2 Loud startup, then quiet

Read full discussion summary

Leading evidence: 'valves opening up' (1 discussions report identifying this cause; no attributable repair resolution). Across 1 matching discussions, the most frequently mentioned possible cause is 'valves opening up' (1 discussions; 1 report identifying it and 0 suggest it). The most frequently discussed action is 'Adjust over' (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 · 3 captured posts examined · 1 partial discussions

Compare 2 other evidence results

Adjust over

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
There is a simple mod that many have done where the clamps on the crossover pipes behind the "T" for the tips are bolted on are loosened and then adjust over to one side, and then you can tune the loudness to your liking by adjusting how much the clamps cover the open slot between the two muffler sides.
Original post Read captured discussion
987.2 Loud startup, then quiet

Run car rich as well as altering the valve timing

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
running the car rich as well as altering the valve timing for a few seconds in order to rapidly heat the catalytic converters up.
Original post Read captured discussion
987.2 Loud startup, then quiet

Frequently discussed actions (2)

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

Adjust over

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
There is a simple mod that many have done where the clamps on the crossover pipes behind the "T" for the tips are bolted on are loosened and then adjust over to one side, and then you can tune the loudness to your liking by adjusting how much the clamps cover the open slot between the two muffler sides.
Original post Read captured discussion
987.2 Loud startup, then quiet

Run car rich as well as altering the valve timing

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
running the car rich as well as altering the valve timing for a few seconds in order to rapidly heat the catalytic converters up.
Original post Read captured discussion
987.2 Loud startup, then quiet

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.

valves opening up

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
cars is caused by the valves opening up on cold start and then closing when it goes quiet, but this is incorrect.
Original post Read captured discussion
987.2 Loud startup, then quiet

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.

3 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

Planet-9: 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: 20261027T201111Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1Original post

Hi there! For a few years now, I drive a 987.2 . Love the car! But I hope one of you can help me out, I'm currently changing a few things, bigger wheels (997 4S 19") and a KW suspension kit V3 (ordered today ). Making it like I always wanted it to be! Now there's one more thing I would like also, when I start her up cold, it is really brutal but after a few seconds it is quiet again. Does it have valves or something standard? Is there a way to always have that sound without a full replacement of the exhaust system? An affordable way ? I don't have the sport exhaust, no buttons inside ... Thx!

POST 2Original post

That is normal on any Porsche , PSE or not. It is for emission purposes, and what you are hearing the is the ECU running the car rich as well as altering the valve timing for a few seconds in order to rapidly heat the catalytic converters up. Its literally creating a fireball in the cats to get them hot. There is a myth that is constantly circulated around on the forums that this noise on PSE cars is caused by the valves opening up on cold start and then closing when it goes quiet, but this is incorrect. Exhaust valves have nothing to do with this sound, and the valves on PSE do NOT open on cold start. The sound is identical even if you were fix the valves either open or closed permanently, or in your case where the exhaust has no valves at all There is a simple mod that many have done where the clamps on the crossover pipes behind the "T" for the tips are bolted on are loosened and then adjust over to one side, and then you can tune the loudness to your liking by adjusting how much the clamps cover the open slot between the two muffler sides. Do a search for " Porsche free exhaust sound mod" and bunch of threads and even YT videos discussing it with details should come up

POST 3Original post

Thank you very much for your detailed explanation. Im happy someone with knowledge responded ;-). And I will search for the tip you gave me. Have a nice day!

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