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The 991 engine doesn't sound nearly as good as the 996 at idle

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18 captured repliesDiscussion pagination complete · Source accounts, not a confirmed diagnosis
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YOUR RESEARCHThe 991 engine doesn't sound nearly as good as the 996 at idle

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Your car was probably built to $85k car standard and regardless what it's current used value is, that engineering, parts, quality control, etc...

The 991 engine doesn't sound nearly as good as the 996 at idle
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Run 991 doesn't sound like

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A properly running 991 doesn't sound like that.

The 991 engine doesn't sound nearly as good as the 996 at idle
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Leading evidence: 'Use value is' (no explicit attributable resolution; this is a reported action or suggestion). Across 1 matching discussions, The most frequently discussed action is 'Run 991 doesn't sound like' (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.

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Run 991 doesn't sound like

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Suggestion

A properly running 991 doesn't sound like that.

The 991 engine doesn't sound nearly as good as the 996 at idle
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Run 991 doesn't sound like

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Suggestion

A properly running 991 doesn't sound like that.

The 991 engine doesn't sound nearly as good as the 996 at idle

Use value is

No successful repair reported for this finding.

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Performed · outcome unconfirmed

Your car was probably built to $85k car standard and regardless what it's current used value is, that engineering, parts, quality control, etc...

The 991 engine doesn't sound nearly as good as the 996 at idle
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18 eligible posts · 0 unverified posts · 1 discussions match the subject in their title or opening post.

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Generation: 20261026T155324Z · outcome-qualification-6. Deterministic extraction; no AI model inference. How we use sources

POST 1 / ORIGINAL POSTEROriginal post

Had my 996 windows open at a stop light. Next to me was a 991. I know nothing about that 991 engine but it must have direct injection. I could hear it pinging and tapping like a diesel's direct injection all the way in my car. It sounded pretty bad while my car just purred and rumbled. 15 years newer and $70,000 more, it definitely sounded worst at idle than my 996 to my ears. I'm obviously biased, but the pinging and tapping really was very noticeable at least to me. Ambient was only 78 degrees outside, stop and go traffic.

POST 2Original post

Must have been something really wrong! A properly running 991 doesn't sound like that. Idle is a deep, low rumble.

POST 4Original post

who cares what they sound like, its how they run that matters

POST 5Original post

Quotes source post: 13610593

The Camry runs great. Congrats

POST 6Original post

Quotes source post: 13610430

With sports exhaust the flat six sounds great in both cars at idle Without it, it does sort of sound flat

POST 7 / ORIGINAL POSTEROriginal post

Quotes source post: 13612006

Maybe this 991 was broken like someone said. I definitely could hear a diesel-like direct injection tapping coming from the 991 engine compartment at idle. It sounded bad and unworthy of a $90,000 car.

POST 8Original post

Quotes source post: 13612069

The 9A1 motor has its own bore scoring issues I believe.

POST 9Original post

Quotes source post: 13612103

And I predict 29 other modes of failure. Just give the aftermarket a little time . . .

POST 10Original post

Direct injection with the engine under tray removed. No big deal just injectors pulsing at 2500 psi

POST 11Original post

Was your car $70k less when new than the 991? Your car was probably built to $85k car standard and regardless what it's current used value is, that engineering, parts, quality control, etc... hasn't changed. Your still comparing apples to apples or 911 to 911. That said, I totally agree with the exhaust note. A 996 with PSE is the best sounding factory 911 I have every heard or owned. The 996s don't need the sound pumped back into the cabin for audio gratification either.

POST 12 / ORIGINAL POSTEROriginal post

Quotes source post: 13612424

If that's normal for the 991, that's not progress in my book. It was pretty loud and it wasn't even that hot outside.

POST 13Original post

Quotes source post: 13612103

you're joking. I hope?!?!

POST 14Original post

Quotes source post: 13614152

Sadly no. Top hit from "Porsche 9a1 bore scoring" as reported by the master of the Flat Six himself: https://rennlist.com/forums/997-foru...ability-7.html

POST 15Original post

My favorite 991 exhaust note versus my favorite 996 exhaust note 991 GTS With Fabspeed Valvetronic Exhaust System 996 C4 With Fabspeed Catbypass X-Pipe and Supercup Exhaust System

POST 16Original post

Seems that just about every water-cooled 911 I've ever heard is on the clattery/mechanical sounding side at idle (not counting exhaust sounds). I've always written it off to the cylinder heads being so low and reflecting sound right off the pavement vs being tucked up at the top of an engine bay near the hood's insulation as in most cars. Now a scored cylinder is a different story altogether...

POST 17Original post

When I bought my car I thought it sounded great and always wondered why people would ever want to change out the exhaust. Then one day I looked closely at the window sticker and noticed it had PSE installed. Aha! That explains it....

POST 18Original post

Quotes source post: 13614152

I'm getting a new motor due to cylinder scoring on my 2015 991 S2.

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