00
0 RPM in submenu
OEM Control
Returns the exhaust flap to the factory ECU strategy. The vehicle decides when the flap should open or close.
MG Flasher Custom Code FeatureExhaust Flap
Exhaust Flap
On-The-Fly
Change the supported electronic exhaust flap between OEM, Closed and Open in real time. Use Live Control, the Custom Code Menu or Custom Code Diagnostics without reflashing the vehicle.
New to MG Flasher? How It Works →
Live Control
Exhaust Flap
Connected
Active State
OEM
Factory control strategy
CCM Value
0
RPM
Exhaust Flow
ECU Controlled
OEM strategy active
Interactive explanation only. Actual flap availability and behaviour depend on the vehicle, exhaust hardware, installed Custom Code and operating conditions.
OverviewControl the Flap
Control the Flap
Without Reflashing.
Exhaust Flap On-The-Fly was introduced with Custom Code v7.1 for compatible vehicles equipped with an electronic exhaust flap. The feature lets the driver return control to the factory strategy, request a closed flap or request an open flap in real time.
The selected state can be changed through the MG Flasher app, the steering-wheel Custom Code Menu or the Custom Code Diagnostics page. With supported controls, open and closed states can be sampled before the selection is confirmed.
Three States
OEM
The ECU controls the exhaust flap according to the vehicle calibration.
Closed
Requests the flap closed, subject to the built-in load safety override.
Open
Requests the flap fully open for a freer exhaust path.
Flap States
OEM. Closed. Open.
Each state has a distinct purpose. The correct choice depends on how the vehicle is being used.
01
1K RPM in submenu
Closed
Requests the electronic flap closed. If engine load exceeds the safety threshold, the flap can open automatically.
02
2K RPM in submenu
Open
Requests the exhaust flap fully open, allowing the system to reduce restriction through the flap-controlled path.
Load-Limiter Safety
Closed Does Not Override Protection.
When Closed is selected, MG Flasher can still open the flap automatically if the configured engine-load threshold is exceeded. This reduces exhaust restriction and helps avoid excessive backpressure under load.
The exhaust flap also opens automatically while supported Anti-Lag is active to provide the required exhaust flow.
Requested StateClosed
Actual StateClosed
Low LoadSafety ThresholdHigh Load
Normal Load
The closed request remains active.
Illustrative threshold demonstration. The production strategy is defined by the installed Custom Code configuration.
Control Methods
Choose How You Control It.
Compatible vehicles can manage the same OEM, Closed and Open states through three MG Flasher interfaces.
Live Control
Select OEM, Closed or Open with segmented buttons while the app is connected to the vehicle.
Explore Live Control →Custom Code Menu
Navigate to the 6K root-menu position, confirm the submenu and select 0, 1K or 2K.
View CCM Steps →Custom Code Diagnostics
Read the current exhaust flap status or set OEM, Closed or Open from the diagnostics interface.
Open Documentation →
Custom Code MenuThe OEM Gauge Shows
The OEM Gauge Shows
Every Flap State.
Exhaust Flap On-The-Fly uses the combined instrument-cluster logic of the OEM tachometer and Check Engine Light. The tachometer selects the Exhaust Flap submenu or the desired state, while the CEL confirms the current CCM step.
6K
Exhaust Flap in the CCM root menu
6× CEL
Counted submenu confirmation
0 / 1K / 2K
OEM / Closed / Open inside the submenu
6K is a menu position
The 6K tachometer position identifies the Exhaust Flap submenu. It is not an engine-speed activation threshold and does not select the Open state by itself.
Closed still retains protection
A Closed request can be overridden when the configured engine-load threshold is exceeded. The exhaust flap can also open automatically while supported Anti-Lag is active.
OEM instrument-cluster feedback
RPM Gauge + Check Engine Light
CCM active
Root-menu position
6K
Exhaust Flap
Check Engine LightSlow CEL blinks
The slow blink confirms that the CCM root menu is active.
Step 01 · Root menu
Navigate the OEM tachometer to 6K
While the CEL blinks slowly, move through the CCM root menu until the tachometer points to 6K for Exhaust Flap On-The-Fly.
Selected state
OEM
Behaviour
Factory ECU strategy
Interface demonstration only. Exact button inputs depend on the configured UniRocker or RockerCombo setup. Vehicle support depends on exhaust hardware, ECU software and installed Custom Code.
Automatic Behaviour
Manual Control with Built-In Overrides.
MG Flasher retains automatic actions where exhaust flow is important for performance or protection.
Load Limiter
A Closed request can be overridden and the flap opened when the configured load threshold is exceeded.
Anti-Lag Active
The exhaust flap opens automatically during supported Anti-Lag operation to provide maximum flow.
OEM Strategy
Selecting OEM returns flap decisions to the vehicle’s original ECU-controlled strategy.
Real-Time Sampling
Supported controls allow the user to hear the Open and Closed state before confirming the final selection.
Compatibility
What the Feature Requires.
Availability depends on the vehicle hardware, ECU software, Custom Code version and selected calibration.
Electronic Exhaust Flap
The vehicle must be equipped with a supported electronically controlled exhaust flap.
Custom Code v7.1+
Exhaust Flap On-The-Fly and its dedicated diagnostics were introduced with Custom Code v7.1.
Supported ECU Software
The installed ECU software must support a compatible Custom Code release.
Feature Enabled
The feature must be available and enabled in the installed Custom Code configuration.
Best way to confirm
Connect the MG Flasher app and check the feature list for your exact vehicle.
FAQ
Exhaust Flap On-The-Fly FAQ
What does Exhaust Flap On-The-Fly do?
It lets compatible vehicles select OEM, Closed or Open control for the electronic exhaust flap without reflashing the ECU.
What is the difference between OEM, Closed and Open?
OEM returns control to the vehicle’s factory strategy. Closed requests the flap closed but retains the load-limiter safety override. Open requests the flap fully open.
Does Closed keep the flap shut under every condition?
No. If the configured engine-load threshold is exceeded, the safety logic can automatically open the flap to reduce exhaust restriction.
What happens when Anti-Lag is active?
On supported configurations, the exhaust flap opens automatically while Anti-Lag is active to provide the required exhaust flow.
Can I control the flap from the MG Flasher app?
Yes. Compatible Custom Code v7.1+ configurations can present OEM, Closed and Open as segmented controls in Live Control. The same states can also be set from Custom Code Diagnostics.
What does 6K mean in the Custom Code Menu?
6K is the root-menu position used to identify the Exhaust Flap submenu. It is a visual menu position, not an engine-speed activation threshold.
How do I select a state inside the submenu?
After entering the Exhaust Flap submenu, 0 RPM selects OEM, 1K selects Closed and 2K selects Open.
Does every BMW support this feature?
No. The vehicle needs compatible electronic exhaust-flap hardware, supported ECU software and an appropriate Custom Code configuration.
Ready to Start?
Control Your Supported Exhaust Flap with MG Flasher.
Check your engine, download the app or open the official feature instructions.