good morning all! I thought i'd start a new thread to see if i can get some help/insight on what might be a different problem with my PSE. This all started yesterday. Here's what's going on:

1. when the PSE is in quiet mode, there is no problem.
2. when the PSE is in loud mode (yesterday), there is a rattling sound in the driver side muffler, but the exhaust is still pretty quiet.
3. when the PSE is in loud mode (today), there is a rattling sound in the passenger side muffler, but the exhaust is still pretty quiet.
4. when the PSE is unplugged from the engine bay, there is a rattling sound in both mufflers, but the exhaust is still pretty quiet.

I feel this rules out the exhaust flaps inside the mufflers and the vacuum units on the outside that controls them. That leaves the solenoid/valve inside the engine bay itself. Just wanna check my understanding of how the system works. Take a look at the schematic below:

http://tinypic.com/r/546tme/6

Also, #18 is the vacuum line going to the air/vacuum pump. My understanding is:

when the PSE is set to quiet, #12 is active, allowing air to be pushed from #18 through #16, #17, #8 and finally to the vacuum unit (#7). pressure on #7 then keeps the exhaust flaps closed and the exhaust is quiet.

when the PSE is set to loud, #12 is closed. No air is in any of the vacuum lines, no pressure is exerted on #7, and the exhaust flaps open.

If #12 can't close fully, then the exhaust flaps can't open fully, creating rattling and no real increase in volume. Sorry about the long post, but does this make sense? Thanks for any insight anyone can provide!

 

In my experience with PSE, the biggest source of rattling is part number 7 on your schematic - the little pushrod that comes out of the vacuum actuator. Try using a ziptie to hold it one place - my guess is rattle will go away. Problem is, zip tie means either open or close, can't have both ways. And of course, I'd advocate for open all the time.

Gundo

 

I was just finishing a long reply to you when I somehow deleted it before posting. PM me with your phone number or email and I'll discuss some ways to isolate your problem. I have installed 2 used PSE systems over the past few years, the most recent being last month.

 

thanks for the insight and offer for help guys. apparently i don't have enough posts to PM yet. i did a little pre-lunch troubleshooting and have discovered a little more info. remember that i can't currently get the exhaust to full loud by pressing the in-cabin button or unplugging it:

1. the hose that i have unplugged (in the pic) is the one that goes to the vacuum units attached to each muffler (#7).
2. the engine is running. when i unplug that hose, the exhaust goes to full loud with no rattling.
3. the engine is still running. when i plug that hose back in, the exhaust goes to full quiet with no rattling.
4. the engine is running and the hose is plugged in. when i turn the exhaust back to loud mode via the in-cabin button, the volume doesn't really increase and the rattles return.
5. also, when the hose is unplugged, the valve/solenoid (#12) seems to have the same amount of suction regardless of how the in-cabin button is set.

this tells me that the problem is either #12 or something further upstream, like the vacuum line going to the vacuum pump or the vacuum pump itself. make sense? i'll likely start with replacing #12 since it's a $25 part.

 

can you post a schematic with clearer resolution please. i cannot read the part numbers

 

here's the raw tinypic image:

http://oi46.tinypic.com/546tme.jpg

 

If I understand correctly, the mufflers work fine when you attach and unattach the vacuum hose to them (so they go to loud with the hose disconnected (no vacuum to them) and go to quiet when the hose is reconnected (vacuum is sent to them). So I would say that rules out the muffler diaphragms being a problem, and rules out the vacuum source being a problem, and points to the solenoid valve. It must be stuck in the open position, which passes the vacuum through both with and without power to it. This doesn't explain the rattles you're getting at the mufflers. You may want to replace your solenoid first (Sunset Porsche quoted me about $35 for solenoid) to see if that fixes things before chasing your tail looking for rattles.
In my case, after recently installing a used PSE, I was getting an annoying vibration/screeching sound from the right tail pipe area. After a lot of investigation, I finally found that one of the metal brackets that are welded to the 2 tailpipes had developed a fatigue crack, and was vibrating metal-to-metal. I took the muffler to a local welding shop equipped for stainless steel welding, and solved the problem for $40.

 

agreed about the solenoid. i just order mine from pelican. now i have to play the waiting game with USPS to find out.

porka, i can't respond to pm's yet. try to unplug the same hose that i show in the pic and see if your problem goes away.

 

The pushrod for the actuator can rattle indeed. Similar situation with some OE & aftermarket turbo integrated wastegate actuator rods. In that case, the OE's have resorted to applying a small weight to the rod itself to dampen it.

 

check the metal straps connecting the 2 exhaust pipes at the end of the muffler, it's quite common for them to break (a hair line crack) and this will cause a rattle. The broken straps needs to be welded.

 

at this point i'm pretty sure it's the solenoid since i can make the noise come and go at will by playing with the vacuum hoses. also, the noise would alternate from one side to the other. hopefully i'll have the new part by tuesday, then i'll know for sure!

 

does anyone know a place in san fran i can get my car up in the air for a diy inspection?

 

If you don't find something, you might want to consider investing in a set of ramps ($40 at Harbor Freight) so you can get the rear end up higher for inspection of your exhaust system, unless you want to do it with the wheels off.

 

I would try to find an independent muffler shop or an oil change location first thing in the AM and see if they will rack the car for $25 to allow you to look under it.

 

the solenoid actually arrived today. i just replaced it and no more rattles! hurray!