Charger Forums banner

1 - 20 of 40 Posts

·
Registered
Joined
·
296 Posts
Discussion Starter · #1 ·
What are you guys doing with the EGR setting and also the o2 sensor has o2 heater and o2 sensor what settings are you using with those.
thanks,
spittle
 

·
Registered
Joined
·
3,886 Posts
What are you guys doing with the EGR setting and also the o2 sensor has o2 heater and o2 sensor what settings are you using with those.
thanks,
spittle
I still don't under stand what EGR is. I know it stands for Exhaust Gas Recirculation, but I don't know why you would need to disable that. But I disabled the 02 sensor and 02 heater and that is supposed to keep you from getting check engine light if you have longtube headers, and so far it has worked for me.
 

·
Registered
Joined
·
622 Posts
I still don't under stand what EGR is. I know it stands for Exhaust Gas Recirculation, but I don't know why you would need to disable that.....
At Part to WOT the EGR sends some exhaust right back into the intake. There is a port in the head or intake that sends the gases back in usually. The SMOG folks figure if burning the mixture once does not cut it, "we'll run 'er through again boss".

Typically, we don't want our cars running on exhaust, but New Air and Fuel! Much as we can Cram in there. :)

I used to always cap the EGR when they were vacuum operated.

We need someone with a gas analyzer to see the effect on A/F from disabling it to know for sure that there are no negative effects.
 

·
Registered
Joined
·
14,728 Posts
what a lot of people dont realize is egr is either vacuum or electronically operated. Never will egr be used if your on the throttle at all . It is used to reduce spark knock in vehicles with off center spark plugs as the flame front has to move throw the whole compression area, and also for emissions of course too. But either vacuum or elec it is shut off under throttle so dont trip about it hurting performance, it doesnt.
 

·
Registered
Joined
·
622 Posts
what a lot of people dont realize is egr is either vacuum or electronically operated. Never will egr be used if your on the throttle at all . It is used to reduce spark knock in vehicles with off center spark plugs as the flame front has to move throw the whole compression area, and also for emissions of course too. But either vacuum or elec it is shut off under throttle so dont trip about it hurting performance, it doesnt.
So on a Charger we can shut it off with no ill effects?

(other than when it is SMOG time)?
 

·
Registered
Joined
·
330 Posts
But either vacuum or elec it is shut off under throttle so dont trip about it hurting performance, it doesnt.
So why do I keep hearing about people wanting to shut it off? what'st he benefit?
 

·
Registered
Joined
·
622 Posts
Well...

So why do I keep hearing about people wanting to shut it off? what'st he benefit?
Anything you can do to get More Air and Fuel in the cyclinder builds power.

Shutting off the EGR will prevent the intake from sucking up any nasty old exhaust gases = more clean new stuff for more umph :)
 

·
Registered
Joined
·
330 Posts
Anything you can do to get More Air and Fuel in the cyclinder builds power.

Shutting off the EGR will prevent the intake from sucking up any nasty old exhaust gases = more clean new stuff for more umph :)
Makes sense, but if it shuts off at WOT, is there a significant difference?
Would you get better throttle response at lower levels?
 

·
Registered
Joined
·
14,728 Posts
So on a Charger we can shut it off with no ill effects?



(other than when it is SMOG time)?
as long as you dont have any spark knock at idle and the light stays away with code reader yea, you'll be fine. Smog time put it back to stock.

So why do I keep hearing about people wanting to shut it off? what'st he benefit?
If they have long tube headers, it can sometimes effect the system. But mainly it is due to the old foogey's fromt the 60's that dont understand electronics on the newer cars. Its the same myth as driving with your tailgate down increases gas mileage when that is actually completely opposite.

Most vehicles dont even have egr anymore. Most vehicles with electronically controlled camshafts (aka, zetec, vetec, vvt) use the exhaust cam to control and redirect exhaust flow without use of an exhaust system.
 

·
Registered
Joined
·
622 Posts
Hmm

Makes sense, but if it shuts off at WOT, is there a significant difference?
Would you get better throttle response at lower levels?
EGR was designed to begin opening at part throttle and be fully open at WOT. This because if you put a big dose of exhuast in early, your motor would run like heck, so they introduce it little at a time.

I do not know how the EGR is provisioned on the 5.7 hemi, so I cannot tell you: A) When it begins to open, B) When it is fully open and C) If the opening is linear or progressive.

Do we have any emission geeks that know?

(I will try disabling mine tomorrow)
 

·
Registered
Joined
·
24 Posts
So why do I keep hearing about people wanting to shut it off? what'st he benefit?
The reason some have been asking for the EGR off option is that they have already removed the EGR and are getting codes and CELs from HAL. So Diablo has fixed it to where HAL no longer sees the EGR and now you have no codes. Why have they got rid of the EGR? Some have want Aftermarket intakes and exhaust that do not support the EGR and like the statement above. We want fresh air not recirculated air. You need Oxygen, fuel , spark, and combustion to get the piston to move. The cleaner and denser the air the better the performance. Exhaust gas is also hotter than the air coming in, therefore it also increases the IAT. Though I doubt that the heat increase is very much, but when you have to fight for every increase in performance you look everywhere.
 

·
Registered
Joined
·
622 Posts
Alright

OK,

I'm gonna drop a line on the Predator forum asking if the option Quits Opening the EGR, or Quites reporting codes if it is unplugged.

Either way, I'm getting rid of it! (will link whatever the Mikes answer)
 

·
Registered
Joined
·
24 Posts
To be honest from what I have read and seen I could not tell you one way or another. I have seen a post from Mike at Diablo stating that they only made HAL ignore the EGR sensor, yet I also saw a post that someone spoke to a tech a Diablo and they say that they actually turned the EGR off. My best guess is that if you have the EGR wait to take it off. Log a run with it on and the EGR option untouched, make a run with the EGR still on but disable it in the Diablo program, then take it off and make a run. That way you can see what if any gains or problems you do have. I always love the before and after that way I can actually see where my money is going. Just my .02
 

·
Registered
Joined
·
3,886 Posts
After one of you tries it and data logs it let us know how it goes. I don't know if I want to disable it yet.
 

·
Registered
Joined
·
24 Posts
Well we finally got a response from Diablo on these questions. If you disable the EGR and the O2 sensors with the Diablo you are actually turning the system off. That means that the EGR will not work and the rear O2 sensors will not work. Hope this helps.
 

·
Registered
Joined
·
2,069 Posts
EGR theory: Under very hot combustion temperatures, nitrogen reacts with two byproducts from combustion and forms Nitrogen oxide (NO). After being released into the atmosphere, it picks up another Oxygen and becomes Nitrogen dioxide (NO2). In the presence of sunlight, it combines with other compounds like Hydrocarbons and forms smog.

Since exhaust gas is inert (very stable) it doesn't really burn again. So by being re-introduced into the combustion chamber, it will lower combustion chamber temps enough so that the Nitrogen will not react with the other byproducts and is passed unchanged out the tailpipe thus not contributing to smog.

Now, since exhaust gas doesn't burn, it doesn't exactly help with combustion. At higher RPM's, this really isn't noticeable, but at idle, the re-introduction of exhaust gas can cause a very rough idle and can cause stalling if to much is introduced into the combustion chamber. (stuck open/partial open condition).

If it's always off (Predator option), you should always have a smooth running engine at all RPM's, however, you are contributing to more smog, how much more I'm not sure because I have no clue how efficient these EGR systems are.
 

·
Registered
Joined
·
24 Posts
.... so turning the system off is good? so thats another reason for me to get the Diablo? lol
1. It is how you want to look at it. If you are performance oriented then yes turn it off. If you are environmentally worried then keep it on. If you are having idling issues or partial throttle issues turn it off.

2. If you need an excuse to buy it then add this to the list I guess. I did not think I needed it before I had it, but after installing it I have to have it and am addicted to the damn thing. : )
 

·
Registered
Joined
·
660 Posts
FYI Mike gave a direct response about this, saying there is NO relation to throttle response and EGR operation. The parameter was put there at the request of several who either disabled their ERG's or were planning to for various reasons. Yes, in theory fuel/air burns more efficiently than exhaust gas, but it really doesn't make that much of a difference that you can feel. In short, if the reason you're disabling the EGR is for performance, it probably isn't worth it.
 

·
Registered
Joined
·
10,665 Posts
EGR valves are designed to be fully closed under WOT. They also do not function until the vehicle hits prime operating temperature. Ported Vacuum switches were used in early years to control EGR funtion. Then manufacturers switched to different controlling devides such as solenoids and actuators. Late model vehicles use an electronically controlled solenoid which opens and closes based on signals from the ecm. The ecm uses reading for engine load, the throttle position sensor, o2 sensors, knock sensors, and coolant temp sensor to determine when and how much to utilize the egr valve.
 
1 - 20 of 40 Posts
Top