Intake Manifold Swirl Flaps Removal / Delete
What are swirl flaps?
Swirl flaps are also known as tumble flaps or intake manifold runner flaps. They are small butterfly valves situated within the inlet manifold (intake manifold) just before the cylinder head intake ports. This device can be found in most of the modern diesel and petrol automotive engines.
The swirl flap is made from stainless steel and is smaller than the intake runner. That helps the air to pass around the swirl flap when it is “closed”. The main role of the swirl flaps is to control and regulate the fuel to air ratio and to improve torque and emissions.
How do swirl flaps work?
As we said above, swirl flaps are intended to help the engine for better fuel-air mixing into the cylinder. They also help for more power, better torque at lower speed and reducing certain toxic emissions.
The swirl flap position is regulated by an electrical or vacuum-actuated servo mechanism. This mechanism is controlled by the ECU (engine control unit). Typically, the swirl flaps are closed at idle or low speed. That way, they create a swirl (additional turbulence) in the intake manifold. That swirling effect improves combustion when engine RPM is low, improves emissions and helps for better torque.
As engine speed increases, for example after 2000 rpm, the swirl flaps become at a fully opened position. That way, they are parallel to the airflow and present no resistance. In other words, at higher speed, the swirl flaps have only a little effect on engine performance, so they allow the engine to function on its maximum power.
What are the problems with swirl flaps?
The swirl flaps are some of the most problematic components of almost every engine from every manufacturer. They are known to fail, degrade and disintegrate as well as they cause serious problems and damages on your vehicle’s engine. Here are some of the biggest problems that swirl flaps are causing:
Mechanical failure
Some early model vehicles, especially BMW’s were fitted with swirl flaps that became brittle and could easily fracture over time. In other words, those swirl flaps were prone to failure. In addition, the small metal screws holding each swirl flap to the spindle were not stable enough. They could become loose and break away.
As you know, the swirl flaps and their screws are situated within the intake manifold. Their location is a prerequisite for any broken part of the flap or the screw to enter the combustion chamber. This mechanical failure often leads to catastrophic engine damage such as damaged cylinder head, valves, injectors, pistons, turbo, etc.
Carbon and oil deposits
Another serious problem is that the intake swirl flaps often fowl due to the intake manifold tarry carbon deposits. In other words, swirl flaps usually clog with soot or become damaged because of problems with EGR system (exhaust gas recirculation system).
Carbon from the EGR system and oil from the breather system create carbon build-up on the swirl flaps. This makes the swirl flap bigger and reduces the internal size of the inlet manifold. As a result, carbon and oil deposits cause poor MPG, worse performance and worse fuel efficiency.
Electronic failure
Most modern manifold designs include an electronic actuator. Its role is to open and close the swirl flaps when it is needed. If those actuators and the position sensors fail, swirl flaps can stick in a closed position and hinder your vehicle’s performance. In a case of detecting an electronic failure with the intake flap operation, the engine control unit (ECU) may report an error code and display an engine fault light on the dashboard. In addition, such type of fault often places the vehicle in a “limp home” mode.
Swirl flaps removal / delete via ECU remapping
Many people are interested in swirl flaps removal via the ECU because all the problems that we have mentioned above cause extremely costly repairs. Not only that but the swirl flap systems are expensive to replace and some manufacturers supply only the whole intake manifold.
We, from AJ Tuning, offer the best custom swirl flaps removal /delete service. We deactivate the swirl flaps by disconnecting them from the ECU and removing their functionality. After that, we modify the intake manifold system and reprogram the ECU to work without it. Our swirl flaps removal / delete solution allows you to remove physically the intake manifold swirl flaps, position sensors and actuators if you want. Or you can choose only to disable the electronic actuator function, so you can leave the swirl flaps in place.
Benefits of swirl flaps removal / delete via ECU remap
Our swirl flaps removal solution has many benefits – here are some of them:
- Increased performance and better fuel efficiency
- No more engine fault codes occurring
- No more engine management warning lights on the dashboard
- Your vehicle will work without any “limp home” mode
- No need to spend a lot of money on a new unit or costly repairs