How to: reduce the rich condition of a cold start.

[EdKiefer]

here article on modding IAT and ECT sensor inputs .

http://www.autospeed.com.au/cms/A_110350/article.html?popularArticle



you need to be careful your not changing timing and fuel at same times.
Also many vehicles have multiple ECT sensors, generally one for ECU fuel amounts and you could have ones for radiator fan switch on temp and also gauge temps, rarely are same sensor used for all 3 .

[Laurentiu]

I guess it does make sense if you live in a very hot place that never sees very low temps.

[Thymeclock]

Originally Posted by Laurentiu

I guess it does make sense if you live in a very hot place that never sees very low temps.

The car still has to warm up to operating temperature - and it will, quite quickly in a warm climate, with no additional prompting.

It never ceases to amaze me what some people will do to save 10 cents worth of gasoline - and/or think that they can re-engineer their vehicle such that they can control every aspect of it.

But maybe that's what much of this list is about.

[mwebb]

you recite EGR theory but have no understanding of how it works
for real

so
in a nutshell
EGR flow reduces combustion pressure and by so doing reduces combustion temperature , thereby reducing NOX formation , which is it's primary function

and
EGR gases are INERT and their presence in the combustion chamber DOES EFFECTIVELY REDUCE COMBUSTION CHAMBER VOLUME
therEby REDUCING ENGINE DISPLACEMENT

which results in the need for more throttle for the same amount of GO
which also REDUCES SUCTION THROTTLING LOSS

which adds up to IMPROVE FE while EGR is functional
these are the FACTS

IF you defeat your EGR your FE will suffer and your system WILL PRODUCE MORE NOX than it would if the EGR was functional

there is nothing to be gained and much to be lost by defeating the EGR
you do not have to believe this or understand it for it to be true.

and it is a violation of Federal law



i dont even believe there is ANY pumping losses with egr disabled and removed. yes it is true that egr increases the throttle opening. but did you stop to think why it does that? it's because the egr dilutes the incoming air with inert used up air that has no combustive value. the egr air simply takes up space in the intake manifold and combustion chamber that would normally have been filled with fresh clean air. in other words, you need X amount of air and X amount of fuel to maintain X amount of speed. with egr on or off you are still using the same amount of air and fuel to go the same speed. the only difference is that some of the air is diluted and the throttle is held open a bit more resulting in less timing. this doesnt magically reduce the combustion chamber volume. it simply renders some of the air that is mixed in, un combustable. and as such it lowers combustion chamber temps. lower cc temps? that doesn't sound good for FE to me. and it isnt. so yes with egr working the throttle is held open more, but you are getting less clean air. the 2 cancel each other out. in the end the same amount of clean air enters the engine, with egr on or off, it doesnt matter. only difference is, ignition timing is being retarded a bit with egr on from the throttle being held open.

i get better mileage with the egr removed and my resistor in place, then with the egr properly functioning. and i havent had a check engine light in a few thousand miles that was egr related. and my scan gauge does show increased ign timing during the same drive with i have egr disabled. and my mpg display shows increased mpg's.
i would hazard a guess that egr is nothing more then an emissions control device. it actually increases fuel consumption on my engine. not a good thing for an ecomodder.


keep in mind also that i don't have a little metro engine. maybe things work differently on small vs larger engines.

V6 chrysler feeds EGR into a central location in the intake
or
has EGR passages to each cylinder ?
because the only possible way EGR could reduce FE in your engine is if your engine
was Feeding EGR gases in un equal amounts to various cylinders
as the -
early 4 cylinder honda accord did when passages to 3 and 4 clogged...
and the 3.8 windstar has the same condition ...
but
chyrsler ? i do not think so .
i will have that answer on Monday -

[Arragonis]

Get a block heater. It has other benefits too like warm toes in snowy weather.

[C3H8]

Originally Posted by mwebb

you recite EGR theory but have no understanding of how it works
for real

so
in a nutshell
EGR flow reduces combustion pressure and by so doing reduces combustion temperature , thereby reducing NOX formation , which is it's primary function

and
EGR gases are INERT and their presence in the combustion chamber DOES EFFECTIVELY REDUCE COMBUSTION CHAMBER VOLUME
therEby REDUCING ENGINE DISPLACEMENT

which results in the need for more throttle for the same amount of GO
which also REDUCES SUCTION THROTTLING LOSS

which adds up to IMPROVE FE while EGR is functional
these are the FACTS

IF you defeat your EGR your FE will suffer and your system WILL PRODUCE MORE NOX than it would if the EGR was functional

there is nothing to be gained and much to be lost by defeating the EGR
you do not have to believe this or understand it for it to be true.

and it is a violation of Federal law



i dont even believe there is ANY pumping losses with egr disabled and removed. yes it is true that egr increases the throttle opening. but did you stop to think why it does that? it's because the egr dilutes the incoming air with inert used up air that has no combustive value. the egr air simply takes up space in the intake manifold and combustion chamber that would normally have been filled with fresh clean air. in other words, you need X amount of air and X amount of fuel to maintain X amount of speed. with egr on or off you are still using the same amount of air and fuel to go the same speed. the only difference is that some of the air is diluted and the throttle is held open a bit more resulting in less timing. this doesnt magically reduce the combustion chamber volume. it simply renders some of the air that is mixed in, un combustable. and as such it lowers combustion chamber temps. lower cc temps? that doesn't sound good for FE to me. and it isnt. so yes with egr working the throttle is held open more, but you are getting less clean air. the 2 cancel each other out. in the end the same amount of clean air enters the engine, with egr on or off, it doesnt matter. only difference is, ignition timing is being retarded a bit with egr on from the throttle being held open.

i get better mileage with the egr removed and my resistor in place, then with the egr properly functioning. and i havent had a check engine light in a few thousand miles that was egr related. and my scan gauge does show increased ign timing during the same drive with i have egr disabled. and my mpg display shows increased mpg's.
i would hazard a guess that egr is nothing more then an emissions control device. it actually increases fuel consumption on my engine. not a good thing for an ecomodder.


keep in mind also that i don't have a little metro engine. maybe things work differently on small vs larger engines.

V6 chrysler feeds EGR into a central location in the intake
or
has EGR passages to each cylinder ?
because the only possible way EGR could reduce FE in your engine is if your engine
was Feeding EGR gases in un equal amounts to various cylinders
as the -
early 4 cylinder honda accord did when passages to 3 and 4 clogged...
and the 3.8 windstar has the same condition ...
but
chyrsler ? i do not think so .
i will have that answer on Monday -

You just quoted me and then made points which i already made and (mostly) agree with. If you want to state facts then here are 2 for you.

"my car gets better mileage with egr disabled."
"my car has more ignition timing with egr disabled."

i got to those conclusions with a-b-a-b testing.

my engine is set up from the factory to have egr piped in a few inches behind the throttle plate. it is a central location. each cylinder does not have individual egr pipes.

if egr was such a great thing for fe, why do certain engines not have it? my mothers honda crv does not have it. my fathers subaru does not (although the automatic version of that car does). my old vw golf mk3 didnt have it, nor did my even older jetta mk2. you would figure that if egr increased fuel economy in addition to reducing emissions then why would this wonder miracle not be a requirement on every car ever made?

im going to guess at the answer. i think it is because egr was only added in situations which needed a bit of help lowering emissions. OR the auto maker wanted to go for extra CAFE points. that would explain why it's on the automatic versions of some cars but not the manual trans versions. autos generally = more emissions. i could be wrong, its only a guess. i realise that egr comes standard on a lot of manual transmission equipped cars too, though, like the metro for example. but i don't have a metro. I have a stratus, a 2.5L stratus. that's a lot bigger then a metro motor.

you don't have to quote federal law violations to me. that's a pretty good blanket to hide behind though, but i would suspect that half the things people on this website do to their cars and engines are probably violations of the law. it doesn't change a thing.

[comptiger5000]

Whether or not EGR is beneficial depends on the cam profile. Sometimes they have enough "in-cylinder EGR" due to the cam that additional egr isn't beneficial. Other times, there is less of that effect, so it's beneficial (for either FE or emissions, or both) to add EGR.

[EdKiefer]

Originally Posted by comptiger5000

Whether or not EGR is beneficial depends on the cam profile. Sometimes they have enough "in-cylinder EGR" due to the cam that additional egr isn't beneficial. Other times, there is less of that effect, so it's beneficial (for either FE or emissions, or both) to add EGR.

Right , A lot of newer engines with variable value timing don't need a EGR valve but the do the same thing (dilute charge) by varying overlap at low speeds-part throttle just like a EGR does .
If the vehicle runs better and gets better mileage w/o EGR then maybe the ignition timing is not advanced as much as it could with EGR on .

[user removed]

The primary reason for EGR is to reduce peak combustion chamber temperatures which dramatically reduces NOX formation.

That is not a guess.

Federal law provides a $2500 penalty for intentionally disabling emission systems.
That applies to vehicle owners. The penalty for businesses is considerably higher.

If you can advance timing with EGR disconnected then you have other issues.

This is based on 60,000 hours of experience.

I don't read about any significant number of people here who are involved in violating emissions laws, so the rationale of "I do it because every one else does it" seems to be weak logic, and if I did think that I would be very worried about someone in the EPA enforcement section reading about any members willingness to violate emissions laws.

I don't, and I wont, because I understand that when operating properly, emissions controls work fine with my mileage enhancement techniques, and I probably would not come to this forum if I thought the consensus opinion was that following the legal requirements was a matter consensus ignorance of the purpose and the consequences of taking the illegal route, not even considering the fact that from the very inception of emissions controls, beginning with Positive Crankcase Ventilation, in 1963, the significant reductions in airborne pollution has been a positive benefit.

In the early seventies the emissions controls were so poorly designed that many people disconnected them in a flawed effort to increase performance. The principle reason for lower power was lower compression.

As fuel injection took over and precise control of fuel delivery became the norm rather than the exception, EGR started to disappear as DFCO and other operational strategies made EGR unnecessary.

It may see a comeback in the future (EGR) as an essential component of engine power control. Development of HCCI engines has seen significant increases in EGR use.

regards
Mech

[mwebb]

im going to guess at the answer. i think it is because egr was only added in situations which needed a bit of help lowering emissions. OR the auto maker wanted to go for extra CAFE points. that would explain why it's on the automatic versions of some cars but not the manual trans versions. autos generally = more emissions. i could be wrong, its only a guess. i realise that egr comes standard on a lot of manual transmission equipped cars too, though, like the metro for example. but i don't have a metro. I have a stratus, a 2.5L stratus. that's a lot bigger then a metro motor.


ok , so since you do not know ....
and do not seam to want to learn .
i will show you.

your test results are flawed
because what is below is REAL , there is NO disadvantage or downside possible related to using EGR .
EGR does not function at idle or WOT so it does not affect max output


so (once again)
in a nutshell
EGR flow reduces combustion pressure and by so doing reduces combustion temperature , thereby reducing NOX formation , which is it's primary function

and
EGR gases are INERT and their presence in the combustion chamber DOES EFFECTIVELY REDUCE COMBUSTION CHAMBER VOLUME
therby REDUCING ENGINE DISPLACEMENT

which results in the need for more throttle for the same amount of GO
which also REDUCES SUCTION THROTTLING LOSS

which adds up to IMPROVE FE while EGR is functional
these are the FACTS

IF you defeat your EGR your FE will suffer and your system WILL PRODUCE MORE NOX than it would if the EGR was functional
==============================
since your EGR statements are not valid or credible
i do not attach much credibility to your claim that
adding 15% diesel fuel also improves FE statements either .

let us see the test results with the related scan data logs
ready
begin