just wondering....what's the ERG valve do?

Carguylen · Post by **Carguylen** » Sat Jan 14, 2006 8:08 pm

I see some posts saying people need to change it or have changed it. What is it's purpose and what happens when it needs to be changed??

Typrus · Post by **Typrus** » Sun Jan 15, 2006 12:55 am

EGR= Exhaust Gas Recirculation
Essentially, it routes a small amount of exhaust gas into the intake charge. Decreases NOx output I believe. Screws performance from what I know. Screws performance even more when its on but fails.
Essentially, it gets gummed up over time. Eventually the gums can jam the valve. As far as I understand.

Gasoline Fumes · Post by **Gasoline Fumes** » Sun Jan 15, 2006 1:09 am

Yeah, it reduces NOx. And it does so by reducing the combustion temperature. Exhaust doesn't have much oxygen or fuel in it, so it just takes up space in the combustion chamber without actually doing anything. This makes less combustion, less NOx and less power. But it shouldn't really hurt power when you step on it since EGR valves don't work at wide open throttle.

They are also supposed to reduce pinging and increase mileage. All they seem to do in my experience is clog up the intake with crap.

takza · Post by **takza** » Sun Jan 15, 2006 4:09 am

http://www.ec.gc.ca/press/000511_b_e.htm

The science is clear: sulphur in gasoline is a significant contributor to air pollution. Its removal reduces emissions from vehicles and improves the ambient air quality. Sulphur, which occurs naturally in gasoline causes emissions of sulphur dioxide (S02) and sulphates (SO4). It also impairs the performance of the vehicle emission control systems. This results in higher emissions of other pollutants such as nitrogen oxides (NOx), carbon monoxide (CO) and hydrocarbons. For example, when sulphur is reduced from 330 parts per million (ppm) to 40 ppm, the tailpipe emissions of sulphur compounds are reduced by 88% while the emissions of other pollutants are reduced by between 20 and 50% for newer vehicles. In a city like Toronto, the use of 30 ppm sulphur gasoline will result in ambient air pollutants going down by 25% for SO2 and 6 to 7% for NOx, CO and SO4.

Internationally, other jurisdictions are acting to reduce sulphur levels:

* California and Japan already have 30 ppm (average) gasoline -- California is requiring further reductions to 15 ppm (average) by the end of 2002;

* In U.S. smog areas, gasoline with an average sulphur content of about 150 ppm was introduced on January 1, 2000. This gasoline is supplied to about one third of the U.S. market;

* The U.S. is implementing nationwide requirements for 30 ppm (average) gasoline in 2005; and

European Union countries have required 150 ppm (maximum) gasoline since January 1, 2000, and require 50 ppm (maximum) starting in 2005.

3A-C Power · Post by **3A-C Power** » Thu Feb 02, 2006 10:27 am

They can also leak and pass exhaust all the time, causing roughness and poor performance.

Typrus · Post by **Typrus** » Fri Feb 03, 2006 10:10 am

So whats the advantage in taking the EGR system off and blocking both ports? I'm sure that in an engine where the valve is a chunk of carbon it does nothing anyway?

takza · Post by **takza** » Sat Feb 04, 2006 5:20 am

duplicate

takza · Post by **takza** » Sat Feb 04, 2006 5:21 am

The only real advantages are...as far as I know...

* can lose mpg and create more pollution (NOX) if it doesn't work

* for street drivng and mileage...best to keep it working...if it's setup right...doesn't cause problems?

* if you have to pass emissions...you need it

* legally you should have it working

disadvantages....

* for those interested in power above all...don't have to worry about if or how fast it shuts off under WOT.

* one less part to keep working...hard to clean