I have a new-to-me 991.1 C4S that Im totally in love with and am still getting used to all the Porsche quirks (noises, smells, etc.).

One that is really on my mind lately is a whining noise coming from the rear of the car that changes with engine RPM. Its definitely only with engine RPM since it chances when the transmission shifts.

It reminds me of gear noise from straight cut gears, like you got on older Honda/Toyota manual transmissions when driving in reverse. Just not nearly that loud.

Its more pronounced on a cold engine and all but goes away after things heat up.

Im most concerned that its an oil separator starting to go. I should mention that Im really sensitive to car noises, so its totally possible this is just a normal noise too.

 

This is your first 911, right? 911s whine, it's part of their "trademark sound" and while it's not something I would directly compare to a straight cut gear as in an old Honda reverse, I could see the association. The air-cooled 911s are much more pronounced with this.

 

Yes, that's how our cars sound, which is glorious! Especially on a cold crank, while you get going. I'd definitely advise letting the car warm up fully before driving 'in anger' or changing to Sport/Sport+ as well.
On the street it's pretty pronounced but on the track you don't even bother it. Especially the .1s, they love to be revved. You won't break it by switching up at 7k.

 

Thanks for the reassurance. It is my first 911 and I dont think ill ever own anything else again.

The CPO just expired so Im all little jittery now.

I absolutely warm the car up (oil temp AND coolant temp) before driving it hard.

And I am definitely not afraid to rev the engine, just afraid of felony speeding, which is way too easy to do.

 

I hear you. I came from a 996 and the engine/transmission whine was a lot less pronounced. Sport+ gets you 30-40 over posted speeds so quickly, it's crazy. Congrats on your purchase! I came from the BMW world and like you said, I refuse to buy anything else. They are simply fantastic machines.