mihak1994

Hi guys! So I have c43 2019. Love it! Only problem is that i bought it without PE exhaust(pe button).
i love the sound of the car when it opens flaps at 4000+ . No need for louder exhaust or something. Only problem is below 4000 rpm, when i am cruising or if i want to rev the car in idle.. no sound.. is there anyway to have open flaps all the time on stock exhaust? I would love to hear the car all the time and not only when driving hard. I think that pe has electronic flaps, but sport exhaust (mine) has pressure based.
thank you!

cg_tim

+1, interested as well.

MaverickC43

There are options to control the flaps.
I have seen posts on here about it
I think ASR might be one of the companies?
Look through the posts here

W205C43PFL

For some reason the exhaust valve modules (ie. ASR) specifically said that it only works with the PE, so in that does the non-PE have exhaust valves or not or really like you said only pressure based. Here is a good look at the two exhaust: https://mbworld.org/forums/c450-c43-...-complete.html

Cosworth2000

Your non-PE does not have values. Its just a basic exhaust so you can't do anything except upgrade your exhaust. A good one is AWE as all the others are way to expensive.

W205C43PFL

That answer the question on why the modules specify needing the PE.

superswiss

As the thread linked by @W205C43PFL discusses, the PE requires an exhaust module in the trunk that controls the valves, as well as a new wiring harness for the button to control the valves from the center console and coding it in, so that the exhaust is properly controlled based on the current drive mode. The PE is integrated with AMG DYNAMIC SELECT, so it isn't just a different sounding exhaust. The author of that thread if you read it essentially ended up just bolting on the PE w/o valve control and basically kept the valves open at all times. That's certainly an option, but it's not how the PE is designed to work.

The non-PE exhausts are not valved, so the exhaust button in the center console and exhaust control in AMG DYNAMIC SELECT is not there, nor is the module that controls the PE as said.

W205C43PFL

Thanks forum member superswiss.

cg_tim

Hang on a bit, in my C43 non-PE, there's a clear difference in how the exhaust sounds in Comfort vs Sport vs Sport+. On Sport+ I even have pops and bangs and it's clearly louder. So the non-PE exhaust is also integrated with the AMG Dynamic Select. Also when starting cold the sound is pretty loud in any mode (valves open), then after 1-2 min. it gets quieter (valves close). This for me is a clear indication that the standard non-PE exhaust also has controlled valves. The question is how and if there's any option to keep them open at all times.

W205C43PFL

Reasons probably are : pops and bangs are caused by the ECU dumping unburned fuel in the exhaust and retarded timing, sport+ revs higher on idle, in comfort the ECU doesn't do any of that. On cold start your engine is running at higher RPM, the ECU again is dumping unburned fuel to warm up the cats.
Could you do us a favour and actually look inside your exhaust if there are valves at all? You got me curious.

superswiss

Pops and bangs and such are not generated by the exhaust. They are generated by the engine ECU by changing the ignition timing. Specifically, the combustion is extended past the cylinder exhaust valves opening, so fuel burns inside of the exhaust causing the pops & bangs. Sport+ also raises the idle rpm, so making things louder even at idle and you are generally in lower gears and at higher rpm in Sport+.

cg_tim

I'd be surprised if all that would be done by the ECU alone. And I was saying, it simply gets louder overall in Sport and louder still in Sport+. On cold start it's not related to the engine RPM, you can actually feel the difference when the sound changes and gets quieter. I'll look inside and let you know.
And when I say louder, it's any RPM, not just idle, it's across the band.

LE: just looked - no valves that I can see, there's only one pipe each side and there's nothing inside that I could see.

superswiss

It's been reported multiple times that there are no valves in the non-PE exhaust, and even confirmed as far as I know. The non-PE exhaust also doesn't have an H-pipe. Although the C43 PE doesn't have a valve in the H-pipe, only the C63 does. The C43 PE has only left and right muffler valves.

You would see the valves when looking inside the exhaust if there are any.

One of the older threads: https://mbworld.org/forums/c450-c43-...ust-valve.html

superswiss

Also, don't forget there's sound being pumped into the cabin through the speakers and it's louder in Sport and Sport+.

cg_tim

No, I'm not talking about the pumped sound, you can hear that it comes from the outside when the window is a bit down and/or driving past a wall or in a tunnel. I'll try capture it on video and if I get a good result I'll post it here. If it doesn't have valves, then I'm really curious how the sound changes so much.

C43HeartBoost

Having changed out my sport exhaust for an aftermarket one, I 100% can confirm there are no valves. What you are hearing is a function of the ECU changing throttle mapping, shift points, dumping fuel between shifts and in high RPM deceleration, etc.

W205C43PFL

I guess that confirmed it and answered our question.

sdrutledge

Is there any way of disabling this?

W205C43PFL

I heard you can pull a fuse.

W205C43PFL

https://mbworld.org/forums/c450-c43-...ml#post7809148

sdrutledge

Lol that was a long and painful read... So considering I have a FL estate with PE..... I can correlate that to what was said in that post which is that nobody has a clue about whether or not sound is plumbed in 😂

I'll take a look and see if there's a fuse or not...

W205C43PFL

Ya, I mean given an estate is fully opened, the exhaust is loud enough to not be pumped in I think? Same reason some people drop their seats of the sedan and it sounds louder.

sdrutledge

Yah, it's pretty loud. And I'm getting a cete module to open the valves 100% so no need to pump into the speakers if it is....

Here's my fuse box

sdrutledge

Yah, it's pretty loud. And I'm getting a cete module to open the valves 100% so no need to pump into the speakers if it is....

Here's my fuse box

W205C43PFL

Ya I don't see the fuse in question, you might not have it or it might be in a different fuse box. Curious though, most people get ASR, CETE is certainly not talked about often, what made you pick CETE over ASR?