997.2 Sports Exhaust Flap Question

[jackwood]

So, I've just installed a Sharkwerks bypass system on my 997 GTS.

But I have a question about the actual logic of the vacuum flaps on the PSE.

Should both flaps operate simultaneously in all conditions? It's just that I noticed today that at idle the flap on one side does not open and close with the switch. It is permanently open. The flap on the other side clearly opens and closes when the switch is toggled.

Anyone have any experience with this? Or anyone willing to go out and have a look at their GTS or 997.2 with PSE and see if both flaps operate together or independently?

Thanks in advance.

Jack

[Trev450]

My 987S with PSE opens both flaps at the same time. Can't see a 997 being different really.

[m040]

Both valves should open/close the same time.

If one valve is open all the time , then either the vacuum actuator on the exhaust valve is broken or more likely there is a vacuum leak or a line is disconnected.

[c4sman]

Both flaps open on my GTS so you have a fault as described above.

[jackwood]

Thank you very much guys.

Now need to determine whether it is a pipe issue or faulty actuator.

Jack

[c4sman]

If you mean the electronic actuator there is only one of these and it is working fine, as one of the flaps is working correctly, so it sounds like a faulty flap or a leak downstream of the actuator

[jackwood]

Each flap is controlled by a vacuum actuator. It is this that I am talking about.

If there was a leak between the vacuum solenoid and the actuator neither of the flaps would work. It must be a busy diaphram in the actuator on the silencer/muffler.

Thanks

[c4sman]

Makes sense

[jackwood]

Just wanted to update this with some useful info to other users in the future:

So it turns out that one of the vacuum actuators on one of the silencers had a collapsed diaphram. Apparently this was very common on the 997.1 PSE

However, the PET system for the Gen2 cars does not show the actuator separately. Only as part of the silencer unit. These are over £600!!

I took the car into Mike at Sports and Classic again and we ordered the gen1 actuator and he stripped the silencer off and indeed the Gen1 and Gen2 actuators are identical.

He swapped the old one for a new one (£70) and all is good again.

Jack

[chrisABP]

Has this repair made any difference to the sound Jack? Curious as to what you were missing out on...

[jackwood]

Yes, it's made it much quieter

When only one was working there wasn't much differene between on and off. So I just unplugged the exhaust so it was in loud all the time. i didn't want any pressure inbalance in the system with one open and one closed.

So now all is working as it should, I have re-connected the vacuum switch. Noticably quieter with the exhaust switched off. Very much like stock, as you described. And obviously with it swithed on it is loud like it was when it was unplugged. I'm sure it opens and closes a bit when driving around town, which is a shame. I am tempted to just leave it unplugged as I really got used to the noise. It must be loud when unplugged because literally EVERYONE commented on how loud it was when I arrived anywhere

[v8ksn]

Jackwood, not sure if this is the same issue but the sport button on my 997.1 GT3 no longer seems to make a difference, its like the exhaust note change between on and off has been muted.

More annoyingly, the car sounds generally muted around 4k revs when normally it sounds awesome.

Any idea what the issue could be?