In general, some people will reduce the cost of purchasing AdBlue by shielding it . It is common to change the signal to deceive the driving computer by brushing the ECU or adding an emulator to the vehicle, so as to reduce the injection of AdBlue. Another cheaper way is to add a screw to the rear processor's sensor to enable the country's four vehicles to have less or no injection of AdBlue . It seems to save a lot of AdBlue costs, but the late maintenance costs may be frightening.

Long-term non-operation of the SCR system will cause the residual AdBlue to crystallize the pipes and injection nozzles. The long-term lack of liquid immersion will reduce or even damage the life of the parts in SCR system . What's more ,the catalyst will lose its effect and the cost of replacing SCR system parts is much higher than the cost of normal use of AdBlue, which in turn increases the cost of the owner.

Now the shielding method can basically be divided into two types, one is the full shielding , and the other is the semi-shielding .

1. Full shielding

Means that re-writes the computer version of the engine ECU so that the AdBlue is not injected in aftertreatment and will not cause the vehicle's speed limit torque failure.

What is the problem with this shielding method for a long time?

First, if the vehicle is a air-assisted aftertreatment system, then the injection nozzle will not work if the aftertreatment does not work, and no gas will come out which is very likely to cause crystallization and particulate impurities in the exhaust gas to block the nozzle.

The other is that the pump does not work for a long time, the AdBlue in the pipeline will be very easy to crystallize and the pump is blocked which lead to the internal fitting is extremely easy to damage.

Secondly, if the aftertreatment system without air-assisted, the injection nozzle needs cooling water and AdBlue to cool down. After full shielding, AdBlue and cooling water will not work and the nozzle will burn out after a long time.. 

2. Semi - shielding

 is to reduce the consumption of AdBlue, and usually by changing the device on the hardware .

Such as adding a screw to the temperature sensor activates the sensor position so that the sensor always assumes that the discharge is normal. The amount of AdBlue injection is reduced and the quality of the exhaust gas is not up to standard, so that the detection quality of the nitrogen-oxygen sensor is not up to standard which will limit the engine torque. In this case, the ECU program needs to be re-written. 

Vehicles that use semi-shielded aftertreatment may not have any problems at first. It feels that the vehicle is driving normally and the after-treatment system is normal. However, after running for three months or six months, the vehicle power will be significantly reduced .Because the catalytic efficiency of the muffler has been seriously affected as well as the blockage of the muffler will become more and more serious. It will be effective to start cleaning several times and the muffler must be replaced later.

All in all, the diesel vehicle with SCR system have to use AdBlue to achieved effective reduction of exhaust emissions . EverBlue as an professional AdBlue manufacturer always committed to reducing vehicle exhaust emissions and provide the best AdBlue solution for the customers. The main products include AdBlue ,AdBlue Production Machine ,AdBlue Dispenser and so on.

AdBlue is used in cars, trucks, buses and heavy-duty diesel engines equipped with Selective Catalytic Reduction of Vehicle exhaust gas aftertreatment systems, which are consumables that must be used in SCR technology, along with SCR catalysts. Harmful nitrogen oxides emitted by diesel engines are converted into harmless water vapor and nitrogen and the main components of the SCR system include the catalyst, the AdBlue injection unit,  AdBlue container and AdBlue dose controller. Almost all heavy-duty automakers in Europe, the US and Asia, including China, also equip vehicles with selective catalytic reduction systems with AdBlue working fluids to meet new NOx emission standards (eg Euro IV, Euro 5) AdBlue and Together with SCR technology, engine performance and fuel consumption can be optimized, and diesel consumption can be reduced by up to 6%, significantly reducing costs.