ElVerde07

Hi There,

I'll make an introduction post later, but quick question for you 997ers out there. Just picked up a 997 c2s and it is a beauty. The only thing "weird" that's happening is this sound after driving, after shutdown.

After driving, even very short distances, once the car is parked and shut down, approximately 1 minute later you will hear a loud (sometimes louder than others) pop sound. Its a deep pop, like if you were to tap on a live microphone to test if it is on. It will just do this once, then nothing else.

At first I thought maybe the brake pads were sticking to rotors, then suddenly releasing. Or maybe some cooling system was shutting down. Or maybe I'm just being hyper paranoid about my new car.

Any thoughts? Thanks in advance everyone.

PTParks

Can you narrow down the location? front? Rear? Have you stayed in the car until you hear the "pop" to see if the source is interior or exterior?

ElVerde07

It definitely sounds like the rear. I'm hesitant to say I'm positive, but 98% sure.

I have heard it from inside the car. The loudest one I've heard was actually when I was sitting in the car for what it's worth.

mikeborden

Do you have PSE,porsche sport exhaust?

ElVerde07

I believe so...apologize i'm very uninitiated at this point and no expert.

Chrome tips, inner tip slightly smaller than outer tip.

The car is equipped with sport chrono pkg, and when in sport mode the exhuast is significantly louder also.

Is this the sport exhaust?

mikeborden

I believe so.

For whatever reason, someone can chime in, I believe what you are hearing is the PSE valves either opening or closing. I run with my PSE off most of the time, so I"m not sure if it's keeping the valves open or closed. I hear the same thing as well.


So, I wouldn't be too worried about it.


Mike

ElVerde07

That makes sense. I've only had the car about 4 days, and it just sounds so damn good with the sport mode enabled. I've been driving it, on and off, with that system the whole time, and probably more often on.

It makes sense that maybe the valves are storing up some backpressure or something, and that is causing the valve to "pop" open or close after shutdown.

Any other input would be helpful to confirm that, but it sounds like a good theory.

jhbrennan

You could disconnect the electrical switch so that PSE is on all the time and see then if the "pop" goes away when you shutdown.

slicky rick

Do you have a bose sound system? With a rear subwoofer? Pop goes the magic dragon...electrical gremlins turning off causing a surge that makes the sub go pop.

ltcjmramos

Not fully aware how PSE may work on other 997s, but in my GTS there is a specific button to activate the PSE. Hitting Sport stiffens up the suspension, and in my PDK-equipped car, changes the shift pattern (holds gears longer, quicker shifts). Don't think Sport has anything to do with PSE.

david

This is correct.

The throttle mapping is also changed in the 6MT.

PSE and S-PASM are two different switches.

I've never heard the popping from PSE that the OP describes and suspect that it may emanate from the sound system like Rick suggested.

ElVerde07

I don't have the bose system. Not even sure if the car has a subwoofer.

This happens after the car is shut off and after I have exited it. Seems like a long wait for the stereo

ElVerde07

I'm starting to agree regarding the sound system. Happened once this evening after the engine wasn't running. I was playing with the stereo in the garage, and when I turned off the key and got out... "thump".

Then once more without key in the ignition. After a cycle of locking/unlocking doors... "thump". At a loss guys.

ElVerde07

FWIW, the manual on my 997 says that, for cars equipped with Sport Chrono and PSE, the sport button activates the PSE. If the car is not equipped with Sport Chrono, there is a specific button just for PSE.

Little Green

Fold down you rear seats. If there is a big box there that is your subwoofer. See if the sound changes or you can hear it better with the seats folded down. It should eliminate that being the problem as it should be easy to hear if it's emminating from there