Welcome to RennTech.org Community, Guest
To all 996 owners with PSE, especially those with a 4S.
I think my 996 C4S exhaust behaves oddly. I think it's a fault but you might tell me it's normal behaviour. The problem is that I've always had this 'fault' on my car so I don't know if it's a fault or intentional behaviour. If you have the same car, perhaps you can shed some light on this.
When I start it, it's noisy and sounds great. It quiets down as it runs for the first 5 mins.
I have the PSE system and when I press the button you can audibly hear the exhaust note change - quieter when on and louder when off. Default is off so loud.
Here's the rub. Up to around 1500rpm it's got a good noise then it fades out to the point where it's so quiet it's like driving my partners Yaris. If I keep accelerating, when I get to around 3500rpm the exhaust suddenly gets loud again. I mean it's immediate - like someones flipping a switched marked loud. It sounds great.
It happens in 2nd and 3rd gears most noticeably and the PSE is in the 'off' position. If I have the PSE button on, then it's just quiet all the time and that works fine.
So why the silent spot?
I did read somewhere that German market cars might have had a system that turns on and off the PSE at certain speeds to prevent people driving round residential streets with a loud exhaust but information is thin and I don't think I was ever on UK cars.
I have also had a small go at checking vacuum pressure at idle on both sides of the Y piece in the engine bay but both hold good pressure. One side has only a microscopic leak but not enough to cause this kind of issue.
I am looking to shave some weight off my 02 with factory PSE. My question is,will a fabspeed ( or any) muffler work with the factory PSE set up? Is it just a matter of removal of oem and replacement with aftermarket? plug and play as its been called? Thanks in advance
This will be my first post, thanks for a great forum !
I've recently purchased a exhaust system from Design911 in the UK which has the valvetronic function on. This is said to replicate the PSE which my car does not have factory installed.
Wired it up and put the vacuum hoses, tested the system and it works fine.
Over to the issue for my car:
When starting up the car, the neutral positon of the valves is open, which means a lot of noice from the exhaust.
When switching this by the solenoid, sending vacuum into the system and the valves closes. This means less sound.
But when the valves is closed the car wont run properly at the RPM range of 5500-7000 RPM's there is also fault codes for misfire on cylinder 2.
The strange thing is that this works perfectly when the valves is open. I've tried two differnet vacuum sources, into the ressonator and also for the left hand side cooling system vacuum solenoids. Without any differnce. I tried to run vacuum directly to the vacuum actuators on the exhaust without any difference and also tried manually applying vacuum and using a one way check valve to keep the vacuum while not connected to the cars vacuum line. No vacuum leaks, no fault codes when driving with the valves open.
Same result every time. So have anyone had some similar issues to their car ?
Thanks in advance for any help !
Hi Folks - a UK forum newbie here with a tech question for the collective, if I may?
I have an 07 C4S with the sports chassis option, sports chrono and and X51 factory upgrade. This means it only has a sport switch, which activates the PSE and softens the psm (no PASM due to the sports chassis pack).
The PSE is having issues though - essentially it doesn't work properly. On start up the valves are open, but as expected when the vacuum builds up they close. However they don't open when the sport button is pressed. I recently replaced the solenoid as I tested it and it had failed and for a couple of times, the new solenoid worked, but now its stopped.
As part of the replacement process, we tested the voltage at the solenoid plug with the sport button on and off. With it off, the plug registered and 12.5v with it on, it dropped to about 8v and the pse worked. After it stopped working, we checked the voltage at the plug again and this time it showed 14.5v when off and 10.5v with it on. So clearly the voltage isn't dropping to 0 as it should do and 10.5v is too much to switch the solenoid. Having been in communications with a couple of people on a UK forum, the feeling is that it's most likely a bad earth causing the volts not to drop to 0.
Has anyone on here experienced a similar issue? Could you suggest any tests that I could run in order to identify what the cause could be?
I'm thinking a straight forward earth to checck would be the engine loom earth near to cylinder 3?
Thanks in advance for your advice and assistance.
New to the forum - just joined - so I hope this is in the right place. This is all in reference to a 2013 Cayenne GTS. I've got three questions I hope someone can help clarify.
First, I've been reading a bit about the "cut off" between 25-50mph (these numbers fluctuate depending on which forum you are in) regardless of if the PSE is turned on. Is this something that is true? I'm pretty sure I can hear this cut off, but ever since I read about it, I can't tell if it's legitimate or just in my head (Baader-Meinhof Phenomenon type scenario) This post talks about how to remove that by bypassing a diode: http://www.renntech.org/forums/tutorials/article/86-remove-pse-cutout-in-2-minutes-no-tools-required/ If all is true, anyone have any resource on how to finagle this diode on the Cayenne? Where is this diode/relay? Does this mod work for the Cayenne?
Second, it looks to be about 600TU to install the PSE if you don't have it, but 150 TU to install just the button (model depending). They didn't put the selector button in until 2014, so, does anyone know if you can have it wired in to the 2013? I'd rather look like an idiot here before going to the dealer.
Third, does anyone have or know of a reputable place to get the full factory manual for the car?
Thanks in advanced!