[vinzcast21]

some cars have an update where the flap will not open after some time when doing cold start. for the x40i models

[MmmmmM2]

FYI with MPPSK installed, you do not have this problem.

[DrGadget]

Originally Posted by F30ZHP

FYI with MPPSK installed, you do not have this problem.

I have MPPSK installed and while the left pipe with exhaust flap opens in Sport modes (once the engine is warm), it does not in Comfort and Eco modes unless one accelerates hard. I use Carly for BMW Pro, and open the flap in Comfort mode once the engine is warm. I mainly do freeway driving, and so having the flap open helps with power and efficiency. Both exhaust tips are therefore the same colour.
Closed: Open:

[MmmmmM2]

Originally Posted by DrGadget

I have MPPSK installed and while the left pipe with exhaust flap opens in Sport modes (once the engine is warm), it does not in Comfort and Eco modes unless one accelerates hard. I use Carly for BMW Pro, and open the flap in Comfort mode once the engine is warm. I mainly do freeway driving, and so having the flap open helps with power and efficiency. Both exhaust tips are therefore the same colour.
Closed: Open:

Interesting. Both my tips are the exact same color and my car is stock.

[DrGadget]

Originally Posted by F30ZHP

Interesting. Both my tips are the exact same color and my car is stock.

Ah yes ... but the small production run (100 of them) ZHP model has the following as standard, and you may drive it mostly in Sport modes.
•Black Kidney Grills
•Carbon Fiber Mirror Caps
•Carbon Fiber Rear spoiler
•M performance power kit
•M performance exhaust
•Limited slip differential (lsd)
•Rear diffuser
All ZHP are RWD (75 manual 25 automatic)
Only 100 produced

[ctp435i]

good info

[Wut36293]

Thanks

[BigJack75]

So what is the secret to get the exhaust valve to stay open on f36 models?

[guruoftechnology]

great

[DrGadget]

Originally Posted by jack10525

So what is the secret to get the exhaust valve to stay open on f36 models?

See the response here:
https://f30.bimmerpost.com/forums/sh...6&postcount=35

If you have Parking Assistant, do not fall for the suggestion to remove fuses 146 and 147 in the trunk as PA will be disabled ... but yes, the flap will stay open. Pulling the flap actuator plug will keep the flap open, but another person posted that after 24 hours the ECU disabled the actuator, requiring $ervice centre intervention. Others have written about using a JB4.

Over to you .....

[Nikopoup]

Hi guys. I want to ask you a question. I have a 340i with the akrapovic exhaust system. A friend of mine has a 328 2012. He asked me to give him my stock exhaust. We made a quick experiment. We placed (not installed) the 340 muffler and connected only the actuator. He put sport + but the valve didn't open. I believe that without the gas pressure it can't open but I am not sure. What do you think?

[ypat]

my 330 has stock black exhaust so I can't see any dirty

[smithf80]

Originally Posted by Nikopoup

Hi guys. I want to ask you a question. I have a 340i with the akrapovic exhaust system. A friend of mine has a 328 2012. He asked me to give him my stock exhaust. We made a quick experiment. We placed (not installed) the 340 muffler and connected only the actuator. He put sport + but the valve didn't open. I believe that without the gas pressure it can't open but I am not sure. What do you think?

It's electronic, it doesn't need any pressure, however, some people have reported that the valve doesn't open without a slight tap of the throttle.

[ASACHOO]

Originally Posted by otay

This is great. Maybe this sticky should be expanded / modified to include all FAQs for noobs?

- Exhaust on one side
- No temperature sync button
- Whirring noise when opening car door (fuel pump priming, i believe)
- What happens if I use regular gas

What else?

haha a noob like mew to this forum could use all the help he can get!

[ASACHOO]

yess! this is helpful!

[godofzeus]

Originally Posted by smithf80

This question comes up all of the time, so I have asked a moderator, Dackelone, to sticky this so it can be at the top of the forum for everyone to see, although I'm sure this won't stop people from asking still.

It is completely normal for exhaust gas to come out of only one of your two exhaust tips, and for only one to look dirty most of the time.

This is because the exhaust on our cars is valved, meaning it has a "flap" inside one of the pipes, and can be controlled electronically by the car for various reasons. In most cases, the flap will be closed, and this is the default setting for both Eco Pro and Comfort mode, this is why you see one tip clean and one tip dirty. In Sport and Sport+, it is open.

Here is a summary of the function of the flap (to my best knowledge):

• Flap closed on startup to help warm up the cat's faster.
• Flap will open itself when the car reaches idle, and will typically open itself when the car is idling.
• After driving away in either Comfort or Eco Pro, the flap will close, and remain closed unless you give the car hard throttle.
• The flap will remain open in Sport and Sport+ mode.

If you car doesn't do what I described to the T, don't worry, it doesn't mean somethings wrong, the car's computer is very smart, and only under certain conditions will that flap open itself, so if you go out and start your car and it happens to be open, don't worry, maybe your cars already warm, etc, etc.

Hopefully this thread will help put to rest all of the questions about this function so we can all get back to complaining about other small, unimportant things.

Great explanation

[DadzBmer_N2o]

I have the 320i and i saw on my maps config (BM3), a setting for the flap, i still don't know if this has one or if it did anything, but the option was there in the config..

[F30 m3 look]

Originally Posted by Tim2189

Alright guys I am going crazy here
just picked up a 2016 435xi gran coupe and this damn flap will not open!
cold start, idle, sport, sport +
It only opens after 3k during driving

I am trying to get it to open while im not driving so I can disconnect the wire and leave it always open.
on my previous 2015 X6 it was simple, once you start the car, the flap opens and closes testing itself and thats when I was able to disconnect it. It seems this car is different even though the flap and connector are exactly the same.

suggestions on how to open the flap while parked?

Start the car. Warm it up . Switch to sport mode, drive. Flap will open. Get out unplug flap power clip. You’re set it’ll stay open until you replug it. Enjoy!

[LukeBarazin]

Great info

[owen2020]

Very professional

[Torquey]

Originally Posted by BigJack75

So what is the secret to get the exhaust valve to stay open on f36 models?

From what I've read and seen... N55 equipped F36 GC and F34 GT exhaust valves under stock programming are set to open differently than other F3x models. The valve doesn't automatically open when switching to Sport(+), neither does it open while parked and revving high. The car HAS to be in gear and it will only open past ~2.7k RPM. My personal theory is this is due to these two models having hatches instead of trunks. Having the valve open at lower RPMs certainly causes unwanted resonance/drone and it will always be more audible through the hatch than a closed off trunk.

I experienced this with both the stock exhaust and MPE and also with or without MPPK flash on my 335i GT. I was able to keep the valve open all the time initially by twist tying the clip (crude but effective). Then I got the Bimmer Link app which has the option to open/ close flap on demand. But discovered that you have to open and connect the app everytime you restart the car, otherwise it reverts to stock settings. I started disliking the drone around 1.8k RPM, which is pretty much where you're at when cruising on the highway (8th gear). I also find the burbles at decelartion are more noticeable when the car is left to stock programming. So I just put it on 'Auto' under Bimmer Link which is basically stock and have left it at that.

I should add that I do have resonator delete and MPE w/ MPPK.

[Zanity]

I coded my valve to stay open from day 1, I hate the look of one black tip and the other clean like new.