Hey there! I can relate to this, I had a similar issue with my 2019 Cayenne Diesel last year. I have some experience working on cars, but this was definitely something I needed professional help with. My symptoms were almost identical, rough idle, power loss, and that distinctive hissing noise. Turned out it was indeed the intake manifold control switch that was acting up. Took it to my trusted Porsche specialist, and they confirmed it with proper diagnostics. The repair set me back about 465€, but it's been running perfectly since then. What's your mileage? Also, any other warning lights or error codes showing up? This info would help to confirm if we're dealing with the same problem. Quick tip: Don't wait too long on this one, driving with a faulty intake manifold control can lead to bigger issues down the road.

Just had my latest service about 2500 km ago and now at 129571 KM. Thanks for sharing your experience, this really does sound similar to what I'm dealing with. No other warning lights besides the check engine, but the symptoms match exactly what you described. Might have to bite the bullet and take it to the dealership to get it properly checked out. Been trying to avoid that, but better safe than sorry, especially with these symptoms. Did your specialist mention how long the repair took?

Hey again! Yeah, I remember when I replied to your first post, glad I could help. About the repair time, in my case with the Cayenne, it took them about 4-5 hours total. They had to order the part first though, which took a couple of days to arrive. Just to give you a heads up based on my experience, your mileage (129k km) is pretty much in the ballpark where these issues typically show up. Mine was around 115k when it happened. The good news is, once it's fixed, it's usually sorted for good. My car's been running like a dream for the past year, no issues whatsoever. One thing I forgot to mention in my first reply, while they had it open, my mechanic recommended replacing some of the surrounding seals as preventive maintenance. Cost a bit extra (maybe 100€ or so) but definitely worth it to avoid having to open everything up again later. If you're heading to the dealership, might be worth mentioning my case, same symptoms, same fix. Could save them some diagnostic time. Keep us posted on how it goes!

Thanks so much for all the detailed info! Really appreciate you following up with the repair time and extra details. That's super helpful to know about the seals too, definitely gonna mention that when I take it in. I've actually just booked it in at the dealership for next Tuesday morning, and they said they'll need it for the full day just to be safe. A bit nervous about the final bill, but you're right, better to get it sorted now than risk bigger issues later. Your experience with the similar mileage makes me feel better about the whole thing, honestly. Was worried it might be something more serious! I'll definitely keep you posted on what they find and if it turns out to be the same issue. Thanks again for all your help, it's great having someone who's been through the same thing!