Today, most vehicles on the road are fitted with an exhaust gas recirculation valve (EGR valve). This sends some of the exhaust gas from the outlet back into the intake in order to help regulate emissions. Sometimes, this valve can play up, and when it does, it can cause issues with performance, so it pays to know little about this part and what you should do if it is faulty.
What Is the EGR Valve?
When some of the exhaust gas passes back through the motor, it automatically helps to reduce emissions. It is particularly effective when the vehicle is first started from cold as this is when the fuel tends to be very rich. The engine control unit will typically increase the fuel potency at this point to help with atomisation during a cold start. However, as the catalytic converter may not be at full capacity at that point, there is always a risk that emissions at the tailpipe could be quite high. This is why manufacturers decided to add the valve to recirculate some of that exhaust and reprocess the emissions.
What Are the Symptoms?
If the vehicle develops problems with its EGR valve, you may notice several symptoms. For example, the engine may feel sluggish or down on power, and it may take you longer to overtake a slower vehicle. In addition, when the car or truck is at a standstill, vibration may increase, which is associated with 'rough' idling. Also, the check engine light may illuminate, prompting you to take further action. All of these symptoms could be a sign of a failing EGR valve and mean that you probably have higher emissions at the tailpipe.
What Can Go Wrong?
As the valve is a relatively simple device, a failure typically means that it is stuck in the open or closed position. When it's permanently closed, this will increase nitrous oxide, as the engine will basically be out of tune. This will lead to additional ignition or engine knocking. On the other hand, if it is in the open position, too many exhaust gases are cycling back into the chamber. Consequently, there will not be enough oxygen in the mix, which could cause the engine to stall.
What You Should Do Next
As you can see, it's important to maintain a healthy EGR valve if you want to lower emissions and avoid performance issues. So, if you suspect there's something wrong with this valve, take the vehicle to a mechanic for repairs. Contact a mechanic to learn more about vehicle repair.