Swirl Flaps Failure 1.9CDTi Z19DTH

So that the fuel/air mixture is combusted in the CDti engine as quickly as possible and as best as possible, the air entering through two separate intake channels for each cylinder is provided with a swirl. one of these intake channels in each case is equipped in addition with an adjustable swirl flap which is actuated through a lever arrangement by the electric drive module. through the position of the swirl flaps, swirling of the fresh air in the cylinder can be adapted to the specific load conditions of the engine.

In this way the quantity of emitted pollutants and the power can be optimally set up depending on the specific load conditions.

Electric Drive Module EAM-i
EaM-i stands for Elektrisches Antriebs-Modul (electric drive module) with integrated “intelligence”.

It permits an adjustment to any point within the operating angle range. An integrated angle sensor acquires the actual position. In case a deviation with respect to the set point position is detected, this is then indicated as an error to the engine controller. The position of the swirl flaps in the intake manifold itself is not acquired. This can only be  performed indirectly through the angle position of the drive module, for this reason malfunctions at the swirl flaps or at the lever the arrangement are sometimes attributed to the drive module.

The cause for these malfunctions are often stiff or sticking swirl flaps.

Deposits or sticking swirl flaps can be caused by very oily intake or charging air. There are many reasons for this.
• Bad, dirty combustion
• faults in the engine management
• Incorrect software revision of the engine controller
• frequent short-run operation
• Malfunctions in the crankcase vent

When the faulty intake manifold remains in the vehicle and only the drive module is changed, this error will reappear quite quickly.
• Perform an actuator diagnosis of the drive module: if the drive module switches, power supply and drive module are electrically in order.
• Check to ensure that there is a proper link (“lever arrangement”) between the drive module and the swirl flaps.
• Check to ensure that the swirl flaps can move freely. the actuating lever must, after being deflected, return to its initial position within a period of 1 to 2 seconds.
• It must not be possible to move the swirl flaps in the axial direction (see figure).