When is egr valve open

But, what is an EGR? Air from the environment, mostly a combination of Oxygen and Nitrogen, combines with fuel and ignites inside the combustion chamber, temperatures increase and produce NOx emissions. The EGR system works by returning a small portion of exhaust gas to the engine's combustion chambers through the intake manifold, lowering combustion temperatures and therefore reducing the amount of NOx emitted.

It connects the exhaust manifold to the intake manifold and is controlled by either a vacuum or a built-in electric step motor. The function of the EGR valve is to control the flow of exhaust gas being recirculated depending on the engine load. Nitrogen oxides are emissions produced as a by-product from the process of combustion, Nitrogen and Oxygen gases in the air react during combustion, especially at high temperatures. NOx is a major component of smog and can have detrimental affects on human health as well as well as ecosystems and agricultural crops.

Therefore, incorporating EGR systems into the design of a car is important with regards to lowering harmful emissions to save the environment and have a positive impact on human health. Although there are several types of EGR valves, earlier systems use a vacuum-operated valve, while newer vehicles are electronically-controlled. EGR valves operate in a complex environment and are prone to wear and tear.

However, the single biggest cause of failure is the buildup of carbon particles from the exhaust gases along the EGR and intake system passages. Failures can also be caused by a rupture or leak in the valve diaphragm. The symptoms associated with EGR valve failure are similar to those of many other engine management components, and because of this, EGR faults continue to be a source of headaches for many technicians.

However, there are a few signs to look out for, such as:. Given the different types of EGR valves, it is always best to follow the troubleshooting procedures detailed in the service manual. However, there are a few common steps that can help to perform diagnostics:.

In the past, EGR replacement could be done in hours. Now, EGR replacement can take up to 8 hours on some passenger vehicles. Our qualified technicians have built up a wealth of knowledge that helps them diagnose EGR system failures quicker, and helps to reduce the cost of EGR repairs. For further information please call us on 03 You can improve your fuel efficiency with an EGR delete.

Another symptom of a bad or failing EGR tube is rattling noises from the engine bay. If the EGR tube breaks or comes loose, it can cause rattling noises as a result of the metal tube vibrating. The noise may be quiet at idle, and become more noticeable when accelerating. What are the symptoms of a failing EGR valve? A faulty EGR valve can cause problems with the flow and operation of the EGR system leading to performance issues including a reduction in power, reduced acceleration and decreased fuel efficiency.

It can also cause vehicle emissions to increase. This range does not include taxes and fees, and does not factor in your specific vehicle or unique location. Rough idle. It is not uncommon for EGR valves to malfunction and become stuck in the open position. As a result, engine temperatures often rise to dangerous levels. Fortunately, an experienced mechanic can easily fix a clogged EGR pipe.

The solution involves detaching the EGR pipe and spraying the inside with carburetor cleaner. This substance loosens up any deposits, which the mechanic then scrubs free using a metal-bristled brush. The same contaminants that can clog up your EGR pipe also accumulate on the valve itself. Over time, those substances make it more difficult for the valve to open and close properly. The valve may even become stuck in a partially open or partially closed position.

As you can imagine, both of these scenarios wreak havoc on the performance of your EGR system. An EGR valve that sticks in the closed position will fail to allow any exhaust into your engine.

As a result, engine temperatures rise, often resulting in knocking or pinging noises. An EGR valve that becomes stuck in its open position allows too much exhaust into your engine. This extra exhaust often causes the vehicle to idle more roughly than usual or even stall out entirely.

In some cases, a mechanic can fix the issue simply by cleaning any deposits off of your EGR valve. If the build-up has led to mechanical damage, however, you may need to have an entirely new EGR valve installed. The EGR valve plays a key role in both emissions control and engine performance.

For more information about the state of your EGR valve, contact us at Dualtone. San Diego, CA Dualtone will be closed for the following holidays:. Call us Today!