ERG valve

fock you are a foctard fix your polluting pos you are causing smog ya foctard

h u r c a s t

I have my ERG Valve back in my car. Of course, the extra 100 gallons of gas I have to use each year adds far more smog than without the valve. But at least you can now go hug a tree.

wanna bet u are a retard

hurc a s t

The EGR valve is used to reduce combustion chamber temperatures. High combustion chamber temps can produce oxides of nitrogen..... this is the component of smag that reacts with sunlight and turns into a brown haze - and it's not good for your lungs. While the thought that increasing fuel consumption may be bad for the environment may seem reasonable, it is our tailpipe emissions that are the concern.

I need to add that the EGR flow is also used to eliminate engine "ping" during acceleration. This allows timing to remain advanced (producing better power) while reducing the chance of damaging preignition.

It's not that the idea is either a bad one or a failed one.... it is that increased fuel consumption is a byproduct of reducing emissions.

HTH

Thanks for the input. The ERG valve was created before fuel injection. Carb days. With modern day fuel injection systems, wouldn't it be better to have a clean intake system and let the fuel injection chip control the chamber temperature? I'm not looking to be a smart ass, but I don't see how burning more gas is better? Also, how can reducing the efficiency of a chamber is better?

Much of the US tax policy on autos, is based on MPG. If maximizing MPGs is producing more oxides of nitrogen, is this bad US policy?

Basically, it just the way the chemistry works. Spent exhaust gasses are used to dilute the intake charge while anything they can do with the injectors can only make the mixture rich or lean (adding the inert exhaiust gasses results in no change to the air fuel ratio). Your extra mileage was experienced because less "pedal" was required for the same results... but the expense was the higher combustion temps that cause a major component of pollution.

On older vehicles, EGR timing and function was neanderthal by todays standards and was the cause of rough idle, poor throttle response and any other number of driveability concerns. EGR systems are not a perfect cure.... with current technology, it is the only viable cure we have. The engineers could limit timing advance to reduce chamber temps but the power/mileage hit would be greater than what we see using EGR. Fattening up the mixture would also be counter-productive and increase HCs as well as costing even more gas than the EGR.

Not a cure nor a panacea, the EGR system is simply the lesser of all the available evils.

Again, just looking for information, if you dilute the amount of air/fuel going in to the chamber, you would need more RPMs to get the same HP than a chamber without dilution.

Do you have a source that I could review that showed lowered combustion temps create less pollution?.

I used to build racing motorcycle engines, and found that the better gasses flowed in the intake and exhaust systems, the better the power and efficiency of the engine was.

My 2 cents:

I was told once to think of the EGR function in a modern vehicle as a way to reduce engine displacement while cruising, when power is not needed. Since exhaust is essentially inert, it takes up space in the cylinder without changing the air/fuel ratio...

I can't argue this point much one way or the other but in my car (which has a problem clogging the EGR lines every once in a while) I don't see much fuel economy difference either way. Maybe it pings a little easier when it's clogged...

PoD

You doubt my veracity and then you want me to do your friggin' homework....

Googling "EGR valve" yields about 149,000 hits. The three I am including are pretty good about explaining it. It has nothing to do with combustion efficiency and nothing to do with power produced... it has everything to do with the air that we breathe. If you don't feel that the device fulfills it's design intensions or if you feel that the brown shit hanging in Los Angeles Basin has nothing to do with cars, why on earth would manufacturers be installing these devices on cars and why on earth would the EPA be demanding reduced emissions?

As Paul points out... why would we want to produce more horsepower than we require for the task at hand?

Lets see, the EPA made gas sellers put toxic chemicals in their gas to save the air. But; what? The chemicals are now part of most public cities water systems.

Since I still live, I'll hug a tree.

Los Angeles Basin

Do you really live in LA?

The city was filled with smog 40 years ago.

Just ask my parents.

Well; sorry, CA killed them

Google my ass, and I'd best that number.

I'm still waiting for someone to explain why we need to waste billions of gallons of gas to pretend that the ERG value saves the earth. After all, using gas causes global warming.

I forgot, It's just politics. And greed

"Chronos" wrote

Go to smog testing station. Stick sensor up tailpipe. Measure NOx.

Disconnect EGR (not ERG) valve. Measure NOx.

Reconnect EGR valve. Measure NOx.

Oxygen bonds with Nitrogen under high temps (around 2000 F) to make NOx. Keep the overall combustion temp below that, much less NOx produced.

How, by adjusting the amount of gas mixing with the available air? There is an "ideal" (stochiometric) mixture where all the gas and air are burned. Too much = unburned gas out the tailpipe, catalytic converter meltdown. Too little = lean misfires (gas out the tailpipe), and high temps (NOx).

The "tree huggers" loved the old VWs too, due to their great gas mileage, which they assumed meant it was a very efficient engine. Unfortunately, they didn't notice that they were spewing 100+ times more crap into the air than today's cars.