what is an EGR valve and what is its purpose?

Question

i know that it located on or near the exhaust.
I have an Oldsombile Aurora V8. if that helps:)

Answer 1

It makes no difference as to make or model.Most engines only run at 80% efficiency so you have 20% of space in the combustion chamber that has some oxygen in it,it causes the combustion chambers to burn very hot,so we have an EGR valve.
Under light throttle conditions it opens up to introduce inert gases into the combustion chambers this has a cooling affect.The theory behind this is gases called oxides of nitrogen cause smog,by using a EGR valve to put exhaust gases back into the engine to cool the combustion chambers reduces this gas,it neither aides nor impedes combustion.DO NOT UNDER ANY CIRCUMSTANCES DISCONNECT OR DISABLE THIS DEVICE,your car has a cooling fan to maintain engine coolant tempreature,these engines already run at the highest heat level possible,disconnecting the EGR valve will make it run hotter possibly to the point of overheating.

Answer 2

Read above description, but forget the heating part. The EGR valve was developed as a way to reduce pollution. It always detracts from performance. I have been successful at lowering emissions by using either a platinum, iridium, or titanium tip spark plug. It reacts with the fuel,a dn lowers emissions while increasing power output because the fuel burns more completely, and the spark plug tip remains cooler and more ready to firs again. You can remove the EGR valve. On most cars it is held in place with 2 screws (bolts). Clean the thing out with Gum-out, focus on the internal diaphragm, and re-install it. I've only seen a few of them actually go bad. Also, clean out the base from which the valve was removed. If they get TOO clogged up, you will have to use a sharp object to force out the carbon. Sometimes compressed air helps. On cars that DON'T have an electronic monitor of the movement of the EGR diaphragm (something that will trigger a check engine light), I usually just block off the vacuum with a ball bearing or bebe pellet. Usually, more power is produced since the combustion chamber is now cooler. The EGR valve allows burnt exhaust gas to re-enter the intake manifold. Obviously, this causes carbon build-up and dirtying up the inside of the intake manifold. Use the Gum-out to clean the intake, therfore, as well. Smoother power and better economy will result. Good LucK!!

Answer 3

So far both answers are right. The additional purpose of the EGR is to lower combustion temperatures resulting from the lean air fuel mixture and prevent pre-detenation in the combustion chambers. The "pinging" sound that you hear when you run cheap gas is pre-detenation. It is actually caused by the vibration of the cylinder walls of the engine, not a good thing.
Your car has a "Linear Electronic EGR Valve" meaning that it is not vacumm controlled as the older style was. It is controlled by the computer. They are very expensive (about $300) and monitored by the on board diagnostic system and will cause a check engine or service engine soon light to come on.
This is a important component of the engine control system and needs to operate correctly to prevent engine damage, not to mention NOx emissions.

Answer 4

The EGR stands for Exhaust Gas Recirculation. Exhaust gas is routed back into the combustion chamber because the exhausted air is much hotter than the intake air (try touching a muffler sometime). By sending warmer gas into the combustion chamber, the air/fuel mix does not have to do as much work to heat up, and your engine runs more efficiently.

Answer 5

an EGR valve takes burned exhaust gases and recirculated a small portion of them back into the engine. It gets used when there is light load on the car such as cruising and helps fuel economy. Essentially, the exhaust gas is inert and takes the place of additional air and fuel ingested into the engine, which means less fuel is dispensed and fuel economy is made better. The EGR system is frowned upon in performance applications like hot rods and racing because they want the maximum amount of aur and fuel in the motor, regardless of fuel economy

Answer 6

The Exhaust Gas Recirculation Valve is a device that was invented and installed on cars to reduce the exhaust emissions on modern cars. In the past few years they have been replaced on many models by computer controls on the mixture, ignition timing, and valve timing.

Answer 7

EGR The exhaust gas recirculation (EGR) valve uses exhaust to reduce cylinder temperature, which in turn reduces nitrogen emissions

Answer 8

EGR stands for exhaust gas recirculation and it does just that, any gases that are left in the exhaust are recirulated back up to theintake and then reburned

Answer 9

EGR stands for "exhaust gas recirculation" it allows the re burning of exhaust gasses that would otherwise pollute or increase emissions