15 captured repliesPartial discussion capture · Source accounts, not a confirmed diagnosis
THIS DISCUSSION / SOURCE-DERIVED OVERVIEW
Discussion summary
YOUR RESEARCH996 c4s with sport exhaust without switch!
Leading reported evidence
Check c4
Performed · outcome unconfirmed
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 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
Checked my C4 with PSE and it does have XLF on the front page of the service manual.
Leading evidence: 'Check c4' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Check c4' (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.
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
* unless you use launch control off the drive in the morning
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.
15 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: 20261027T022239Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources
i was told when i bought the car it had a pse,
the car sounds great but no switch! does that mean its not a pse?
my questions are 1. is there any way of checking if its a sport exhaust?
and secondly can i have a switch fitted if it is a pse?
thanks
Nas
Probably (not PSE).
Check if the mufflers have a bypass, and if PSE it will be valved.
If it is a PSE, yes. But it probably isn't.
See here for non-PSE bypass info:
Oops linkage failure (I blame a dying iPhone):
http://www.911uk.com/viewtopic.php?t=51776
http://www.911uk.com/viewtopic.php?t=51363
http://www.911uk.com/viewtopic.php?p=561144
http://www.911uk.com/viewtopic.php?t=52160
http://www.911uk.com/viewtopic.php?t=53215
http://www.911uk.com/viewtopic.php?t=54056
http://www.911uk.com/viewtopic.php?t=53002
If the PSE was factory fitted, you will have option code "XLF" on the under bonnet label and front page of service book label.
It can be retrofitted, but expensive.
If if is there, you need to look for this gubbins on mufflers:
Checked my C4 with PSE and it does have XLF on the front page of the service manual. Any way of finding out what the other numbers on the Vehicle ID page mean?
...then it's not got a
factory-fitted
PSE; probably has some sort of mod (documented on here at length in previous posts) or maybe an aftermarket exhaust (maybe even a Porsche item but without the switch fitted, although I'm not sure how that would work with the vacuum).
I wouldn't worry - if you like the sound, just enjoy it; if you had the switch I doubt you'd ever turn it off; I only turn mine off when I'm coming home late (post-midnight) or leaving the house early (pre-6am)... 8)
fwiw..
I have XLF option code and when it was serviced at OPC east london they also confirmed I have PSE from factory fit... however, i have no switch in the car... The service guy did say that the PSE was available with and without switch...
Just to add clarity for future queries...
mine doesnt look like that at all.
maybe it isnt pse..
does that mean its constantly on if there is no switch?
mine is quite on stand still, but give it a little gas it comes to life
Nas, does it look like this photo. This is the PSE fitted to my C4S and is a top quality job. The mufflers are either manufactured or modified by Eisenmann in Germany for Porsche.
PSE (factory fitted or retro fitted) is speed dependant and will go into quiet mode between 30 and 45 MPH (approx). There is a mod (relay removal) to allow it to operate in the loud mode all the time.
As previously mentioned, not all (Porsche OEM) PSE's have the dash switch fitted.
My apologies, that photo I attached of the nice shiny mufflers is the 3.4 996.1 PSE1 design.
Nick B's (although a clone mod) is identical to the 3.6 996.2 PSE2 muffler design.
If you just have a bypass mod (nonPSE) or sports mufflers (third party), then the quiet pach below 2k rpm on partial throttle is entirely due to too little back pressure to utilise bypass.
If the noise is speed dependent (irrespective of gear), then it is valved by PSE or PSE clone.
Sounds like you've got an aftermarket muffler bypass. Downside with them is as GT4 says you don't get the PSE "grumble" at small throttle openings as there's simply too little back pressure for the bypass to have a pronounced effect. Upside is you don't need a switch as there's no risk of waking the neighbours*
* unless you use launch control off the drive in the morning
This is a source reference. Confirm exact model applicability in the original material.
