All vehicles up to VIN AH999999 have it and after VIN BH000001 they don't

Here's info from workshop manual, what it does and when

The TD4 cylinder head and intake manifold are designed to optimize levels of swirl across the engines speed range, and provide a high volume of air into the cylinders. The intake manifold is designed with a lower row of 4 helical swirl ports, and an upper row of 4 filling ports with port-deactivation device. The 8 ports are sealed to the cylinder head and structural camshaft cover mating ports with a shaped sealing ring. The helical swirl port is configured to create optimum swirl for efficient combustion; while the filling port is provided to supply high volumes of air without disturbing in-cylinder swirl. The intake manifold port de-activation device is controlled by the ECM.
Each cylinder is supplied air through the helical swirl port, and when activated, through the filling port. The helical swirl port is always open and directs air from the intake manifold lower port at a tangent into the combustion chamber. The filling port is normally closed, and is only opened during certain engine operating conditions by the ECM. When opened the filling port directs air from the intake manifold upper port, and through the curved intake tracts into the combustion chamber. The intake tracts are cast with the structural camshaft cover, and join the intake manifold upper filling ports to the cylinder head machined filling ports. At low engine loads gas flow is so low that the filling port is closed off. This has the effect of raising gas velocity through the helical port and increasing in-cylinder swirl to the optimum rate. To avoid the risk of the high gas flow creating excessive swirl, the ECM opens the filling port under high gas-flow conditions to maintain consistent optimum swirl across the engines operating range.


Port de-activation is operated by 4-butterfly valves connected on a common shaft within the intake manifold. Each butterfly valve is housed within a corresponding intake manifold upper filling port. The common shaft is connected to a vacuumoperated actuator, and is operated by a solenoid valve under the control of the ECM. The vacuum required for port de-activation is supplied from the engine mounted vacuum pump

Port de-activation (opening of the filling ports) only occurs when the coolant temperature is greater than 10°C, and under the following conditions:
-Engine speed is greater than 1,800 rpm.
-Engine load is greater than 15%.

So they help to start engine when cold and save fuel on low loads.

I don't believe that only reflash of ecu will solve the problem and flaps can be removed. It can be removed and no reflash done but you will have problems and more smoke on cold starts and up to coolant temperature +10C and consumption will grow.
From vin code BH000001 it changed a lot as well as intake manifold without swril ports, ECU, glow plugs, EGR cooler with port, turbocharger, crankshaft position sensor and something else that I don't remember.

DW12 engine up to AH999999
CR DI engine from BH000001

I'm very interested if anyone can modify existing ECU program to deactivate ports and still have good results on starting engine in cold mornings and consumption. I have already fitted newer engine which has intake manifold without ports to earlier vehicle. Left old turbocharger and other related parts except intake manifold which was broken.

I have got an issue with my 2012 SD4 190. This youtube video demonstrates my problem:



Is your explanation of solenoid valve etc causing this issue, where there is a release of pressure/loss of power at 1800-2000rpm? Is there anything specific I need to do to fix it?

Thanks.