Climate change and air pollution are environmental problems caused by the intensive use of petroleum-derived fuels.
Nitrogen oxide (NOx) and particulate matter (PM) emitted from the exhaust of vehicles running on petroleum-derived fuels contribute significantly to climate change and air pollution.
Manufacturers of engines running on petroleum-derived fuel are developing technologies aimed at reducing the emission levels of these harmful gases.
Among the technologies they have developed, the systems most commonly used in vehicles are
EGR (Exhaust Gas Recirculation) and SCR (Selective Catalytic Reduction – AdBlue).
1- EGR
In short, EGR systems are used in vehicles to reduce NOx (nitrogen oxide gas) emissions. It does this by redirecting a portion of the exhaust gases coming from the engine back into the engine's combustion chambers.
When the air/fuel mixture in an engine burns at a very high temperature, it tends to produce greenhouse gases such as nitrogen oxide. EGR cools the gases coming from the exhaust and sends them back into the combustion chamber, significantly reducing the amount of NOx gases released into the environment. Having a functioning EGR makes your truck more environmentally friendly.
As a truck owner, it is important to keep the EGR valve in good condition. Since it has a direct effect on how the engine runs, any issue with the EGR will show up as either increased fuel consumption or reduced performance. That is why it is important to know when it needs to be serviced or replaced. Some of the signs that may point to a faulty EGR include:
Engine Control Unit (ECU):
The engine control unit (ECU) opens or closes the EGR valve to control the flow within the EGR system. The EGR valve connects the exhaust manifold to the intake manifold. The EGR valve is normally closed. There is no EGR flow when the engine is cold, idling, or during hard acceleration. EGR engages during steady cruising under moderate load. If your vehicle's ECU fails, it cannot control this system and the EGR system will not work.
An EGR valve stuck open:
If your vehicle has a mechanical EGR valve and it gets stuck open, it acts as a passage that causes a vacuum leak in the engine. Some of the symptoms of this include rough idling and even a feeling of hesitation when trying to accelerate. When the problem is serious, you will also notice that your vehicle stalls frequently. When the EGR valve is stuck open, it means all of the exhaust will be directed into the combustion chamber, which means there will be too little oxygen available for combustion.
An EGR valve stuck closed:
At the other end of the spectrum, there can also be a valve that is stuck closed and will not open. In such cases, there will be an increase in the amount of nitrogen oxide gas in the cylinders, which will show up as engine knocking.
These are two common problems affecting mechanical EGR valves, and fixing them can be quite costly. All you need to do is find an authorized service center to repair it for you.
Basically, when exhaust gas leaves the engine after the combustion process, the EGR system routes some of these gases back into the engine's cylinders. If the flow of exhaust gases cannot sufficiently return to the engine cylinders, you will encounter various different symptoms that will affect your driving.
The symptoms you may encounter include engine operation where the RPM fluctuates, stalling, rough idling, or engine knocking. Poor engine performance is certainly something to be concerned about in this situation. Your fuel economy will also suffer, forcing you to spend more money at the pump.
When you encounter EGR problems, get in touch with us at TUTKU ELEKTRONIK OTO A.Ş. Our expert team will resolve the EGR issues in your vehicle in a short time, with their knowledge and experience.