Forté Technical tips – Low pressure EGR issues + AdBlue impacting engine performance

Low Pressure Exhaust Gas Recirculation (EGR) is an emission control technology used in diesel engines to reduce the amount of nitrogen oxides (NOx) released into the atmosphere. In combination with AdBlue, a urea-based solution, the EGR system helps to meet strict emissions standards set by regulatory bodies. However, some vehicles equipped with Low Pressure EGR and AdBlue systems have experienced issues related to low pressure, causing reduced engine performance and increased emissions. This technical bulletin aims to provide information on the root cause of the low pressure EGR issue with AdBlue systems and the possible solutions.

Engine performance diagram

Problem

The low pressure EGR issue with AdBlue systems is caused by a blockage in the system due to the build-up of deposits – AdBlue is injected into the exhaust system to reduce the level of NOx emissions. Over time, the AdBlue can react with exhaust gases and form solid deposits that can block the EGR system and EGR cooler. This blockage causes a reduction in the flow of exhaust gases, leading to reduced engine performance and increased emissions.

 

Symptoms

Vehicles with a low pressure EGR issue may experience several symptoms, including reduced engine power, increased fuel consumption, and increased emissions. This can also produce a fault code for Diesel Particulate Efficiency below threshold. When the EGR cooler is blocked and the system operates, pressure in the exhaust increases and the system thinks that the DPF regeneration is not efficient and alerts the driver with a fault code.

 

Solution

Some cases may require the Low pressure EGR and Cooler to be removed and cleaned.

 

Prevention

Preventing the low pressure EGR issue with AdBlue systems involves regular maintenance and proper use of the vehicle. The AdBlue system should be refilled with the correct AdBlue fluid at the recommended intervals, and the vehicle should be driven regularly to ensure that the AdBlue system is functioning properly. Additionally, cleaning the fuel and oil system regularly will help to maintain fuel and oil system cleanliness and maintain exhaust gas temperature.

 

Conclusion

The low pressure EGR issue with AdBlue systems can cause reduced engine performance and increased emissions in diesel vehicles and present DPF soot loading or efficiency fault codes which may not be down to the DPF – the issue is caused by a build-up of deposits in the EGR Cooler system. Regular maintenance and proper use of the vehicle can help prevent the issue from occurring. It is essential to address the low pressure EGR issue promptly to ensure that the vehicle meets emissions standards and performs optimally.

 

Use at every service: