jdubdds24

Ok so I have a 2009 C4S 6spd with Sport Chrono Plus and no PSE button. Apparently the previous owner (i'm the second owner) installed the full PSE exhaust, i have PSE mufflers, tips, all the vacuum tubing routing the valve and everything. There are, as far as I can tell, two things I do not have. One is the 5 button center stack (my current stock stack has "SPORT, PASM, REAR TAIL, PSM". The second thing I am missing is the wiring loom. there is a COV on a bracket on the upper right side of the engine bay near the side of the plenum. I have that valve but only the vacuum lines are hooked up, there is no wiring connected. i searched hi and low and dont see one that maybe just got unplugged. Question...does sport chrono plus (vs regular "sport chrono") have PSE?! And next question,,, i'm going to order the 5 button switch panel for my center stack and then buy the wiring harness. Suncoast has them both for $250 total (which is cheap enough for me to want to do this). Does anyone know the routing for the harness? I'm sure I can get it routed to the back from the center stack, Ive had most of my car apart in pieces already but just wanted something official. The sales rep from the parts dept at suncoast said porsche doesnt like to give out that info... so, thoughts?

And yes the PSE works fine without the button...but I LIKE BUTTONS, ok?!

systech

The normal PSE is wired from the console switch panel via the ECU to a solenoid vacuum valve which switches the vacuum lines to the exhaust valves. The previous owner of my 997.2 installed the PSE exhaust but without any of the wiring or vacuum lines. After installing a backbox bypass I wanted to install the wiring but decided to use the OEM switch panel and a 2 pole latching relay ( one pole for the switch LED, the other to switch the vacuum solenoid) connected directly to a vacuum solenoid rather than via the ECU. This meant the PSE is either ON or OFF as per the switch setting rather than controlled via the ECU on a rev dependent basis (for noise regulations). I ran the wiring down the centre console and through a bung under the ECU to the engine bay because getting it through the wiring loom on the RH side of the engine bay was just too hard. This is all documented on 911UK forum using an idea by DucatiRob... do a search if you’re interested.

jdubdds24

wow I will check it out. Thank you!

Chris M.

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If you are able to find the pins that connect the wires to the back of your switch panel let me know. I tried to use the DucatiRob method referenced above to connect my valved mufflers to a factory switch panel with the exhaust button on it but I could not find those pins. Searched all over, ordered several different versions and none were small enough. I finally gave up and I control my mufflers with the Homelink buttons instead.

systech

I used the Prewired cables with pins that are often used for link connections inside a PC. Not exactly the correct pins but have been fine. Most electronics stores stock them

jdubdds24

ducatirobs post is good but none of the pics load and the links are expired. I'll continue to try to figure it out. I love the idea of have it bypass the ecu and just go straight to the source...

systech

The attached photo should help. BTW you don’t need to use 3 equivalue resistors ..2 will do provided one is twice the resistance of the other ( do a quick search of “voltage divider circuit”). I strapped the resistors across the relevant terminals of the latching relay.