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Hey all, can't find a lot about my particular issue. 2014 991.1 C2S
When I start my car after sitting for a day or two, and activate my PSE, Sport, or Sport Plus buttons, I have no issues at all, valves open as expected and stay open for the rest of that drive.
However, if I drive around for a bit and temps steady, then stop for a short bit then getting back in with the car still warm and I have issues...
After having the car running for a bit (usually oil temp of 90C+ which is where is plateaus) after letting the valves close again, I hit one of the options above and I get a really 'gurgly'/bottle sound that is honestly quite awful and sounds worse than the Cherry Bomb cans you weld in-line from AutoZone.
Anyone have this issue or know how to remedy?
I have seen a few threads to check the vacuum line connections under the deck lid that are little brown plastic valves, but can't find them on mine and now looking again that seems to be on the 997.1/2.
I think this is normal. When I cold start my 991.1 GTS, the sound is glorious for about 15 seconds, then it quiets down a bit. If I drive for a while, stop and start the warmed up car again, the sound is quite sad...
If you are talking cold start vs warm start yes the sound is different.
Not talking about the start at all. Hard to describe I guess.
Basically when I use the active Exhaust valves when the car has been off for a while and "cooled down" I have no issues.
However if I had the PSE on and then just run into the gas station really quick, after driving around for 15min or so and temps are steady, then restart my car and activate the PSE again, the valves seem to not open all the way and the PSE the rest of that drive and for a while will not work correctly and sound horrid. Like there is something blocking the pipes.
Best I can sum it up to is the active valves on my PSE seem to get stuck when the car is hot and makes it sound like I have a cheap *** exhaust system some guy welded in his backyard.
So you have three distinct sounds -- PSE closed properly, PSE open properly, and PSE being weird?
Can you get it to do the weird sound without shutting the car off? Like if you were to go for a drive with valves open, then while driving, close the valves, then reopen them?
Do the valves eventually open up all the way and sound normal when the problem is happening, or is the only cure to have the car fully cool down?
Have you tried moving the rod in the PSE valves up/down to see if the sound changes? Maybe it's sticky/dirty and doesn't fully close? Probably easiest fix would be to disconnect the vacuum lines (and seal them)...
So you have three distinct sounds -- PSE closed properly, PSE open properly, and PSE being weird?
Can you get it to do the weird sound without shutting the car off? Like if you were to go for a drive with valves open, then while driving, close the valves, then reopen them?
Do the valves eventually open up all the way and sound normal when the problem is happening, or is the only cure to have the car fully cool down?
Exactly.
Yes, I can get the weird sounds after driving just as you described. Sometimes I turn it off in a neighborhood or in a drive-thru then when I got back into sport I get PSE being weird again.
Sometimes if I ride out the gear I'm in and hit like 7k rpm it sounds like it opens them up again, but sometimes it won't. Really inconsistent with the "rev the **** out of it" fix
Sounds like a sticky valve. As mentioned above, check the actuator itself -- get a glove and check it when it's hot, too.
I did earlier today with it running (yum exhaust) and it looks like from under the Right one is UP and the left one is DOWN after recreating the sound. I've hit them with WD-40 a few times in the past, but I'm thinking then it's a loose vacuum hose/valve somewhere. Just can't find any documentation on where the 991.1 lines are, mostly just 997 owners with PSE issues.
Have you tried moving the rod in the PSE valves up/down to see if the sound changes? Maybe it's sticky/dirty and doesn't fully close? Probably easiest fix would be to disconnect the vacuum lines (and seal them)...
What do you mean by seal them? I think you are right on the cause though!
I did earlier today with it running (yum exhaust) and it looks like from under the Right one is UP and the left one is DOWN after recreating the sound. I've hit them with WD-40 a few times in the past, but I'm thinking then it's a loose vacuum hose/valve somewhere. Just can't find any documentation on where the 991.1 lines are, mostly just 997 owners with PSE issues.
probably an obvious question but worth asking -- it isn't up/down side to side because of mirroring, right? like one is actuating up/down and the other is staying down?
If you disconnect the vacuum hoses, you would have the PSE always ON (so the exhaust button in the dash wouldn't do anything), with the advantage that you would get even a sportier sound (don't want to get into detail, but when you disconnect the vacuum hoses you get the valves always 100% all the time; whereas with the vacuum hoses connected, the PSE system closes/opens the valves throughout the rev range). It's important that you cap-off the hose-ends so you don't get a yellow warning about a coolant system failure.
If you disconnect the vacuum hoses, you would have the PSE always ON (so the exhaust button in the dash wouldn't do anything), with the advantage that you would get even a sportier sound (don't want to get into detail, but when you disconnect the vacuum hoses you get the valves always 100% all the time; whereas with the vacuum hoses connected, the PSE system closes/opens the valves throughout the rev range). It's important that you cap-off the hose-ends so you don't get a yellow warning about a coolant system failure.
Looked into it, sourcing some ramps so I can use this as a temporary fix until I can get to the root of the issue. However I do live in an apt next to some condos so I try to be quiet aka shut off exhaust when I'm getting home to keep eveyrone from hating me.
Still confused by what is causing them to get stuck like half-open and sound super 'baffled.' I'm thinking some high-temp grease on the valves and ball-joints, then checking all the vacuum lines is in order.
Has to be related to heat as when I start the car up after sitting for 24 hours or so I have no issues, but running it for 20 mins and I can recreate the issue now.
probably an obvious question but worth asking -- it isn't up/down side to side because of mirroring, right? like one is actuating up/down and the other is staying down?
That's a good point! However, I looked when it was off and sitting for a while and they both start at DOWN, then the vacuum pressure pulls the valves UP (shut).
So both should be in sync. I know what my issue is, now to track down the culprit.
In your picture is that the valve on the passenger-right behind the wheel? Or one of the 2 right next to each other, right behind the backbumper in the center?
09-14-2021, 03:03 AM
PSE valves not opened fully when at 90C+
