Why is urea consumed quickly?

Urea consumption standard: A vehicle with China IV emission standard consumes 3-5L of urea when consuming 100L of diesel, while a vehicle with China V emission standard consumes a relatively larger amount, around 5-8L.

Under what circumstances will urea be consumed?

According to the working principle of the aftertreatment system, when the exhaust gas is discharged from the engine, after the temperature of the exhaust temperature sensor reaches 180 degrees Celsius, it will be fed back to the ECU signal, and the ECU will order the urea pump to start working, to build up the pressure to store pressure, and when the pressure reaches the standard pressure, the urea nozzle will start working.

Injecting urea will decompose into ammonia gas and water in high-temperature environments. It then enters the catalytic converter, where it reacts with the exhaust gases. The nitrogen compounds in the exhaust gases react with the ammonia to produce water and nitrogen gas. This completes the entire post-treatment process, ensuring that the exhaust emissions meet the required standards.

What is the reason for the high combustion of urea solution?

1. When the nitrogen oxide sensor detects that the vehicle's exhaust emissions do not meet the standards, it will initiate additional urea injection.

2. Issues with the urea nozzle.

3. Problems with the urea pump, such as internal malfunctions that result in pressure build-up failure. Alternatively, in air-assisted urea pumps, there is a higher likelihood of excessive urea injection.

4. The exhaust temperature sensor sends a signal to the computer board when the temperature reaches 180 degrees, initiating urea injection. If the exhaust temperature sensor malfunctions and starts urea injection before reaching 180 degrees, it can lead to excessive urea consumption.

5. Issues with the quality of vehicle fuel and urea. Poor-quality fuel can result in increased harmful gas emissions from the engine, which requires more urea to participate in the reaction, leading to higher urea consumption.

6. Road conditions can also contribute to increased urea consumption. For instance, driving on hilly or uneven roads for an extended period can cause inefficient combustion within the engine, resulting in poor exhaust quality and higher urea consumption.

7. Engine malfunctions, particularly within the common rail system, can also lead to incomplete combustion and non-compliant exhaust emissions.

8. Computer board program problems usually limit the amount of urea consumption in the after-treatment system. If there is a problem with the computer board program, it will also cause excessive urea consumption in the after-treatment system.

Among the eight reasons mentioned above, three are related to the quality of urea solution, indicating that the quality of urea solution largely determines its consumption. Using poor-quality urea solution not only leads to excessive urea consumption but can also cause nozzle clogging, urea pump blockages, and even engine malfunctions.