[R_C_S_//X3M]

I have a 435i Gran coupe with MPE and MPPK. My exhaust flap does not open on a cold start at all. Car can sit an idle for 10 minutes and the flap never opens. I called my dealership to tell them I think it's faulty and they assured me it only should open at high RPM's. They said flap is controlled by the DME so I am thinking that maybe the DME was reconfigured when the MPPK went in is controlling the flap differently then every other 435 with MPE only?????? I have seen the flap open at cold start for every other 435 (with or without MPE) after about 60 seconds but all those cars did not have MPPK.

Only reason I am even concerned is my wife was following me today and I was in Sport+/Sport and she said there was no smoke coming from left tube at any point and right tube was smoking constantly.

Anyone have a similar set up that can chime in????

[auf Deutsch]

I have yet to see exhaust fumes exiting from both outlets, no matter how long the car has been running, when standing behind it at idle.

Relax, it's normal.

[R_C_S_//X3M]

Originally Posted by auf Deutsche

I have yet to see exhaust fumes exiting from both outlets, no matter how long the car has been running, when standing behind it at idle.

Relax, it's normal.

Ok. Buddy of mine just got his MPE exhaust installed and you can clearly see the flap open up after a minute after cold start. Watch video below. I guess the MPPK changes the flap if everything is in fact normal. Would you mind letting your car idle for a minute and half at cold start and see if you flap opens.

https://www.dropbox.com/s/6wkrbxqafu...48.30.mov?dl=0

[Buckeyes]

I have the MPE and like stated above mine opens after about a minute. You can hear it open and if you use a flashlight you can see it open. I've since done the golf tee mode so it's always open now and equally dirty exhaust tips.

[R_C_S_//X3M]

Originally Posted by Trcb777

I have the MPE and like stated above mine opens after about a minute. You can hear it open and if you use a flashlight you can see it open. I've since done the golf tee mode so it's always open now and equally dirty exhaust tips.

Do you have MPPK as well? That seems to be the variable which may be stopping the flap from opening on my car. That is what I am trying to find out.

[crono06]

Why don't you try this:

After coming home for a drive, put your car in Sport and leave it on. Go out and see if there are fumes coming out of both sides.

[R_C_S_//X3M]

Originally Posted by crono06

Why don't you try this:

After coming home for a drive, put your car in Sport and leave it on. Go out and see if there are fumes coming out of both sides.

I have. At no point while in park whether in Sport or Sport+ is my flap opened. Ever. I can rev to 4500 in Sport and Sport+ and the flap is closed.

[Buckeyes]

Originally Posted by R_C_S_435i_GC

Do you have MPPK as well? That seems to be the variable which may be stopping the flap from opening on my car. That is what I am trying to find out.

I do not. Bms stage 1

[M-terkait]

Originally Posted by R_C_S_435i_GC

I have. At no point while in park whether in Sport or Sport+ is my flap opened. Ever. I can rev to 4500 in Sport and Sport+ and the flap is closed.

maybe its time to openflap mod

[crono06]

Originally Posted by R_C_S_435i_GC

I have. At no point while in park whether in Sport or Sport+ is my flap opened. Ever. I can rev to 4500 in Sport and Sport+ and the flap is closed.

Ah okay. Maybe the next time you're in, show the SA/tech in this way?

It definitely doesn't sound normal that the left flap would never open. Do you notice any black buildup at all on the left pipe?

[R_C_S_//X3M]

Originally Posted by M-terkait

maybe its time to openflap mod

Sounds like shit with MPE and MPPK. Seriously. The drone at around 1500 is terrible.

[zeyad.habeeb]

Originally Posted by R_C_S_//M3

I have a 435i Gran coupe with MPE and MPPK. My exhaust flap does not open on a cold start at all. Car can sit an idle for 10 minutes and the flap never opens. I called my dealership to tell them I think it's faulty and they assured me it only should open at high RPM's. They said flap is controlled by the DME so I am thinking that maybe the DME was reconfigured when the MPPK went in is controlling the flap differently then every other 435 with MPE only?????? I have seen the flap open at cold start for every other 435 (with or without MPE) after about 60 seconds but all those cars did not have MPPK.

Only reason I am even concerned is my wife was following me today and I was in Sport+/Sport and she said there was no smoke coming from left tube at any point and right tube was smoking constantly.

Anyone have a similar set up that can chime in????

I have the same with my car. I never see it open.


After you research, is that normal?

I saw 440i . The flap will open once you switch it to sport mode.

[Logicoeur]

Originally Posted by zeyad.habeeb

I have the same with my car. I never see it open.


After you research, is that normal?

I saw 440i . The flap will open once you switch it to sport mode.

The ONLY way to open it is to go into sport/+. Unless you use an app to code it separately.

[codestar]

I found after the cold start has finished and the idle has returned to normal (1-2mins), even if the car is in sport mode the flap will not open up until you tap the throttle. It's pretty obvious for mine now because it becomes a straight pipe and you can hear a major change in the exhaust note.

Let it idle 2 mins -> switch to sport mode -> rev the throttle a little bit -> NOW check and see if the flap changed.

If it didn't, then take a look at the valve motor. The little clip that connects the actuator to the valve itself came off on mine once and I had to go to BMW to get a new one. It's called a "Fixing Bow". Luckily my local dealer had them on the shelf.

Hope that helps

[Filip3615]

hey, first post. hope I make this right..
I've got a 435i GC as well, only mine is equipped with a supersprint exhaust.
The issue here is that the gran coupe is configured differently than the Coupe (this is what I've read).
The flap on the gran coupe only opens above approx. 2500 RPM in drive IN sport/+
Even if you rev it above 2500 while in N/D it wont open.

Although this can be overridden with a JB4 module where you can choose to open/ close the exhaust through your BC button (left lever behind steering wheel).
Im currently looking for a solution to this too, that's how I found out the above information.
hope this helps somewhat and if anybody finds a good solution, please share!

[doodlebro]

Is the flap controlled by vacuum or electronically? On my car I had power issues because my flap's vacuum line had become disconnected. So the flap wouldn't open and my wastegates couldn't close.

[panaceabeachbum]

I have mppk and mpe and my exhaust flap opened at cold start every immediately until recent MHD flash

[TheShadow]

Get a better axleback and it will always be open. Or get Akrapovic for valves

[Torquey]

I did notice how old this thread is, but was wondering if OP got the issue figured out. I installed MPPK yesterday and MPE today... and experiencing the same issue where the valve does not open while stationary, regardless if its cold/ warm start... comfort/sport/sport+. I've looked into the driver side tailpipe with a flash light and the flap is clearly closed.

The MPE I bought was used and it came with it's own controller and the connector is firmly plugged in. I may swap it with the one from my old exhaust just to see if that changes anything. Also interested in knowing the default valve behavior under MPPK programming. TIA!

[Torquey]

Swapped the valve actuator with my old one and still the same result. The valve doesn't open no matter what mode or what revs.. at least when car is parked. Not sure if that changes under load, but there was no way for me to test that. MPPK install could've very well changed the settings for it.

So I decided to secure the clip that's connected to the valve to the 'open' position with twist ties. Currently it's always open, but the actuator is detached from it with the electrical still plugged in... so for the DME everything is normal. The sound is definitely 'deeper/lower' as it gets dispersed between the two pipes. From the driver seat, it's more prominent, since now the pipe that's closer to me is also making sound. Need to drive around a little more to get the true feel.

Here's a quick clip that I took with the car warmed up (car had resonator delete already):

[Torquey]

Did some more digging into this and ended up getting the Bimmerlink app for ease of opening/ closing the valve (which works great BTW). Looks like F36 Gran Coupe and F34 Gran Turismo are both set to similar valve programming from factory, where it ONLY opens when in 'Drive' and closer to 3k RPM. It does NOT open while in 'Park'/ 'Neutral' no matter how much you rev and/or change to Sport/Sport+.

My personal theory is, both the GC and GT being hatchbacks, the amount of unpleasant resonance aka drone at low RPMs could be heard more easily inside the cabin... compared to sedans which have closed off trunks. I know this personally from having owned Corrados & GTis in the past. I would be curious to know if the BMW engineers set the F31 hatches the same way.