Go Back   EcoModder Forum > EcoModding > EcoModding Central
Register Now
 Register Now
 

Reply  Post New Thread
 
Submit Tools LinkBack Thread Tools
Old 07-03-2011, 07:54 PM   #21 (permalink)
n00b.... sortof..
 
d0sitmatr's Avatar
 
Join Date: Oct 2010
Location: SFL
Posts: 345

silver fire - '03 Mazda Protege5
90 day: 32.52 mpg (US)
Thanks: 37
Thanked 19 Times in 18 Posts
Quote:
Originally Posted by saand View Post
Hi Euromodder
I looked into this idea myself a month or so ago and didn't have much success due to my car's age and I wanted to do it myself so I could continue to tune the best parameters

The thread I started is here. It has some good responses
http://ecomodder.com/forum/showthrea...ion-13824.html

The concept is definitely a good idea, the ECU configuration and design for the whole car is set up for the worst case conditions and some things are set up for drivability at the expense of wasted fuel.

Unfortunately the implementation can be difficult. For my car in particular I have a car that doesn't have the programming connection instead it has inbuilt configuration values. From what I have read you can usually change out the eeprom or connect up a daughter board which will override settings but I personally wasn't willing to spend that much on the modification and there is a risk of killing your car completely so if your doing it yourself I highly recommend getting a second ECU from a wrecker or something like that.
If your getting a chip tuning place to do the work for you there is the disadvantage of you might not understand what they are tuning out so you may not get the best efficiency or they might cause damage to the car (running too hot or something like that)
You can also go down the path of replacing your whole ECU with a customizable version which is often done in racing however it can cost a lot of money for a customizable ECU.

If you have a bit of a search on google you will find some chip tuning web sites and instructions which might help.

As for my solution I will just be "fooling" the ECU by either overriding its outputs or changing its inputs so it does what I want.

Good luck.
@saand
those are impressive numbers on your 626, I know a bit about those cars and they are very hard to tune unless going for more power.

for my protege5, I can have it flashed for the MP3 ECU (or just install an MP3 ECU) and it will clean up my powerband (which bounces every which way, including loose....) along with a gain of 2-3 mpg over stock, according to the several people on mzda247 who have done so.
that would be a good base to start with, then I could maybe have that fine tuned even more to gain every ounce of FE as possible.

__________________
~Mike

  Reply With Quote
Alt Today
Popular topics

Other popular topics in this forum...

   
Old 07-04-2011, 05:18 AM   #22 (permalink)
aero guerrilla
 
Piwoslaw's Avatar
 
Join Date: Oct 2008
Location: Warsaw, Poland
Posts: 3,538

Svietlana II - '13 Peugeot 308SW e-HDI 6sp
90 day: 58.1 mpg (US)
Thanks: 1,056
Thanked 630 Times in 396 Posts
Quote:
Originally Posted by euromodder View Post
Don't kill birds
I don't, unless I want chicken for dinner

Quote:
Originally Posted by euromodder View Post
The software they downloaded to adjust the idle cost 1,x euro .
You don't get remaps for that
It basically enabled them to adjust the idle.
These cars have all the potential built in, but you need to buy/install the software to actually enable them.
It's that cheap? I'll ask at my Pug forum about it, somehow I can't believe that my Peugeot dealer would take less than 50€ for anything, no matter how small... Maybe I'll call him up?

Quote:
Originally Posted by euromodder View Post
Next service, I'll be asking them to switch the OBC to km/L rather than L/100km.
I thought that's a parameter that can be done by the driver? I'll check my OBC when (if) it stops raining.
__________________
e·co·mod·ding: the art of turning vehicles into what they should be

What matters is where you're going, not how fast.

"... we humans tend to screw up everything that's good enough as it is...or everything that we're attracted to, we love to go and defile it." - Chris Cornell

Piwoslaw's Peugeot 307sw modding thread

  Reply With Quote
Old 07-06-2011, 04:08 PM   #23 (permalink)
Master EcoModder
 
Phantom's Avatar
 
Join Date: Jan 2010
Location: Independence, KY
Posts: 602

Blue Meanie - '02 Volkswagon Golf TDI
TEAM VW AUDI Group
90 day: 48.52 mpg (US)

Wife's car - '05 WV Passat TDI

Rudy - '94 Chevy C2500
Thanks: 89
Thanked 46 Times in 43 Posts
It sounds like what the dealership is using is similar to GMs TechII that can change some parameters.

Changing the idle speed can be done via a remap on most ECUs and should have a few lines in the table. On the cars (gas) that I have looked at they have the following:

The Y-axis is:
AC off in drive
AC off Neutral/Park
AC on in drive
AC on Neutral/Park

The X-axis is:
Coolant Temp

The corresponding cells contain the desired idle RPM. This way the idle will be higher at low temps drop down at operating temp then rise a bit at high temp to spin the water pump more for cooling. Also it will bump the RPM up a bit when the AC is on.
__________________
I move at the speed of awesome.


"It's not rocket surgery!" -MetroMPG
  Reply With Quote
Old 07-06-2011, 06:02 PM   #24 (permalink)
Cyborg ECU
 
California98Civic's Avatar
 
Join Date: Mar 2011
Location: Coastal Southern California
Posts: 6,238

Black and Green - '98 Honda Civic DX Coupe
Team Honda
90 day: 66.42 mpg (US)

Black and Red - '00 Nashbar Custom built eBike
90 day: 3671.43 mpg (US)
Thanks: 2,356
Thanked 2,130 Times in 1,444 Posts
So Hondata's s100 is only $195 and allows tweaking of the air/fuel tables on an OBD2 ECU, such as on my 1998 Civic. Lots use it for street racing, of course, but it should be tunable for MPG, no? Has anyone tried it? I'm not ready for such a move yet, but if anyone has tried it or has an opinion, I'm curious.
__________________
See my car's mod & maintenance thread and my electric bicycle's thread for ongoing projects. I will rebuild Black and Green over decades as parts die, until it becomes a different car of roughly the same shape and color. My minimum fuel economy goal is 55 mpg while averaging posted speed limits. I generally top 60 mpg. See also my Honda manual transmission specs thread.



  Reply With Quote
Old 07-06-2011, 11:22 PM   #25 (permalink)
n00b.... sortof..
 
d0sitmatr's Avatar
 
Join Date: Oct 2010
Location: SFL
Posts: 345

silver fire - '03 Mazda Protege5
90 day: 32.52 mpg (US)
Thanks: 37
Thanked 19 Times in 18 Posts
Quote:
Originally Posted by California98Civic View Post
So Hondata's s100 is only $195 and allows tweaking of the air/fuel tables on an OBD2 ECU, such as on my 1998 Civic. Lots use it for street racing, of course, but it should be tunable for MPG, no? Has anyone tried it? I'm not ready for such a move yet, but if anyone has tried it or has an opinion, I'm curious.
Im pretty sure most of your aftermarket tuners come with the ability to tune for power or economy.
__________________
~Mike

  Reply With Quote
Old 07-08-2011, 05:00 PM   #26 (permalink)
EcoModding Lurker
 
Join Date: Apr 2010
Location: charleston, sc
Posts: 9

Smurfback - '01 Chevrolet Blazer LS
Thanks: 0
Thanked 1 Time in 1 Post
This is interestingly a two-edged sword. If you look closely at a lot of the dyno charts for these tuners they show their highest gains below peak. What you are really getting is a broader power curve with more gains down low. (This is generally what I have seen.) That's accomplished by taking out some of the fuel under those parts of the curve. Through the 90's and probably into the 00's manufacturers seemed to be adding a little fuel to the curve to ensure reliability of the motor. This explains how a tuner can give both power and economy simultaneously. To that end, be careful when you go changing your maps for efficiency. Most motors can't take big changes.
  Reply With Quote
The Following User Says Thank You to bgfshrcr For This Useful Post:
California98Civic (07-08-2011)
Old 07-08-2011, 05:21 PM   #27 (permalink)
EcoModding Apprentice
 
Join Date: Jun 2010
Location: New York
Posts: 239
Thanks: 0
Thanked 17 Times in 15 Posts
while most tuner type tune/reflash does improve efficiency , its partly done by leaning A/F at high loads and increasing ignition timing , its tuned for 91+ fuels .

Now for eco uses you want to remap part throttle area, but this area of load is closed loop modes and is mapped to the A/F of O2 sensor . So you have to somehow adjust this or any changes will be reverted, learned back to the ECU O2 closed loop values, which are for most vehicles around 14.7 .

So depending on the unit and type of hardware (reflash, daughter board, piggyback ,etc) this will be a go or no go depending if you can adjust closed loop modes .

Last edited by EdKiefer; 07-08-2011 at 05:34 PM..
  Reply With Quote
The Following User Says Thank You to EdKiefer For This Useful Post:
California98Civic (07-08-2011)
Old 07-08-2011, 08:34 PM   #28 (permalink)
EcoModding Lurker
 
Join Date: Jan 2010
Location: Los Angeles, CA
Posts: 54
Thanks: 0
Thanked 20 Times in 8 Posts
Quote:
Originally Posted by EdKiefer View Post
So you have to somehow adjust this or any changes will be reverted, learned back to the ECU O2 closed loop values, which are for most vehicles around 14.7 .
Sorry, I saw this in the email 'best of' today and just had to comment. There are really three main approaches in altering factory tunes:

1. Reflashing
2. Piggy Back
3. ECU Replacement

Reflashing is a broad term. For many ECU's, there are make/model specific parameters that can be tweaked with factory tools and/or ripped off versions of factory tools.

For even more hardcore reflashing, code in the ECU's is functionally altered. For most makes/models there is a an active community in this area, though some makes/models are easier than others. For example, Suburu and Mitsubishi ECUs have been heavily hacked and reflashing hardware is cheap and readily available. On the other hand, vintage Hondas are often reflashed by taking apart the ECU and replacing masked ROM parts with reprogammable memory chips.

Piggy Backs generally use stock ECU's, but then fool them into doing desired things. They do this by replacing sensor signals. If I under or over report MAF or MAP to an ECU, it's response is going to alter. Piggy backs are less flexible, but often perfectly adaquate for typical light weight performance mods. I change the airbox, VE of the engine is changed, so I need just a scootch more fuel...

ECU replacment is sort of the ultimate in control. These range from inexpensive DIY projects, like Megasquirt, to very expensive replacment ECUs. There is a very nifty line out of Australia that uses FPGA technology and a pictoral scripting type language so that you can, effectively, alter virtually anything that the ECU does.

In order for any of these things to be used to get economy, some considering has to go into where fuel is wasted, and why. When a relatively modern vehicle is 'closed loop', it is almost always running very close to lambda 1.0.

People refer to this as 14.7:1, but that is wrong. The actual air fuel ratio to acheive lambda 1.0 is fuel dependant, it moves around a lot just with altering fuel blends. The ECU is not using AFR, but one or more O2 sensors. The sensor itself measures 'equivelency ratio', or 'fi'. Lambda, the scale we use in engine science, is the recipricol of fi. Until the last few years, most cars used 'narrow band' O2 sensors. That is, they only measured 'fi' over a very narrow band. Basically, 'lambda 1.0 = 450 mV'. If you go richer or leaner, the sensor very quickly shoots to about 1V or about 0V.

So, in those vehicles, the only point that the vehicle knows actual lambda with any confidence is lambda 1.0. To understand why this leads to fuel being wasted, we need to understand why this point is being targetted in the first place.

Lambda 1.0 is the 'stoichiometric ratio' for the fuel. That is, it is the optimum mix of air and fuel for the most thermal energy released. This is why it is relatively easy for a narrow band sensor to detect. If combusion is richer, then there are unused HC's in the exhaust, if leaner, excess O2. This sounds really efficient, but it's not. If you want 'best power', you run richer, somewhere around .86 lambda. If you want 'best economy' you run leaner, around 1.05 lambda.

This is because a combusion engine is not a steam engine. It isn't just about how much thermal energy can be released, but how much mechanical advantage can be gained pushing against a piston with expanding heated gases. Running richer than lambda 1.0 also changes the speed and chemistry of the flame front, so peak pressure is moved to a point of more mechanical advantage. And since fuel is plentiful, all O2 gets used. Conversely, going leaner means that all the fuel can get used which, combined with the changing properties of the flame front, still has reasonable mechanical advantage.

The reason that the car runs at 1.0 is purely for emissions. Lambda 1.0 has two important properties. First, it is a point where certain polutants kind of 'bottom out', go away from that point and things like CO and HCs soar. Second, it peak EGT. Peak thermal reaction means hottest exhaust gas. And that heat is needed for a modern cat to work. In fact, cat efficiency plummets very quickly as you move away from peak EGT.

So, much of the time, the vehicle is targetting lambda 1.0, strictly for emissions. But when you stomp on the gas, this is not the place to be. CHTs are fairly high (proportionally) at lambda 1.0 (they peak just rich of stoich, in the .9's), so if you stomp on the gas and stay there, you won't get best power and you'll have high CHTs, lots of fuel, lots of heat and lots of pressure is basically a recipe for detonation. So the ECU runs richer. Best power not only means more power to do whatever it is you stomped on the gas for, it also means lower CHTs.

But, remember 'narrow band' above? An ECU armed only with this sensor doesn't really know for sure where it is running in this case, so factory tunes virtually always error towards 'richer', which costs power, but also brings CHTs down further (by moving peak pressure, not by actually using fuel as some sort of 'spray on coolant').

Performance tuners lean this out (and potentially shift peak pressure with timing as well). They want the lost power back. But this also means better fuel economy for this mode of operation.

Newer vehicles are much more likely to have a 'wideband sensor', or a better idea of exactly where they are running in the .7 to 1.3 range. So those factory tunes generally waste less fuel in those cases. Though there is generally still some waste. The most cutting edge is to use wideband closed loop at targets other than 1.0, but that is another subject.

But people here already avoid that case. So, while they will get savings, it won't be as much as my lead footed wife might get with the same change.

If you don't care about the environment, better economy is not all that hard to acheive. I've done this with a number of vehicles on the dyno and in test environments, like UC Riverside. Basically, I remove the narrow band sensors and replace them with wideband sensors. I then simulate the narrow band signal for the ECU. Think of it this way, the ECU is targetting 450 mV. On a narrow band, this is lambda 1.0, but if I'm reading the exhaust mixture with accuracy at other points and simulating this signal, I can make 450 mV anything I want. If you slowly shift it towards theoretical best economy and let the ECU's adaptive algorythms catch up, you can typically get some clearly measurable fuel savings for same weight, speed, and distance. If you optimize timing to match, there is more savings still.

But emissions get terrible and you potentially destroy your CAT. On my development 'road bed' I still simulate the narrow band signal, but 'tighter' than a real narrow band. That is, I collapse the normal S curve of a typical narrow band. If you track O2 sensor voltage with an OBD-II scanner, you will typically see it oscilalte back and forth, rich/lean/rich/lean as it chases stoich (lambda 1.0). These swings are nec. for cat operation (you need some O2 to burn), but they are a little sloppy. So by making my stock ECU chase a tighter signal, measured emissions actually go down (because the cat spends more time at peak efficiency). There is a tiny fuel savings, but it is so small that it is certainly not worth persuing for its own sake.

When I run with the non stock ECU, I generally run closed loop even in rich operations, which gives the typical driver a lot of savings, but, again, not so much for folks here.

My point in all this is that there are savings to be had here, but the big Kahuna is off limits unless you don't care about emissions. Still, there are some non obvious things that ECUs do that can also be tweaked for savings. Like tweaking shift points to match your driving habits.

Sorry to just jump in (and somewhat rehash), but it is 'my area', so to speak.
  Reply With Quote
The Following 8 Users Say Thank You to jfitzpat For This Useful Post:
California98Civic (07-08-2011), d0sitmatr (07-09-2011), meelis11 (07-13-2011), Phantom (08-11-2011), Piwoslaw (07-11-2011), SDMCF (10-30-2015), todayican (04-25-2012), Xist (10-31-2015)
Old 07-08-2011, 09:39 PM   #29 (permalink)
home of the odd vehicles
 
rmay635703's Avatar
 
Join Date: Jun 2008
Location: Somewhere in WI
Posts: 3,488

Silver - '10 Chevy Cobalt XFE
Thanks: 395
Thanked 741 Times in 556 Posts
Quote:
Originally Posted by jfitzpat View Post
Sorry, I saw this in the email 'best of' today and just had to comment. There are really three main approaches in altering factory tunes:

Newer vehicles are much more likely to have a 'wideband sensor', or a better idea of exactly where they are running in the .7 to 1.3 range. So those factory tunes generally waste less fuel in those cases. Though there is generally still some waste. The most cutting edge is to use wideband closed loop at targets other than 1.0, but that is another subject.

But people here already avoid that case. So, while they will get savings, it won't be as much as my lead footed wife might get with the same change.

If you don't care about the environment, better economy is not all that hard to acheive.

But emissions get terrible and you potentially destroy your CAT. On my development 'road bed' I still simulate the narrow band signal, but 'tighter' than a real narrow band. That is, I collapse the normal S curve of a typical narrow band. If you track O2 sensor voltage with an OBD-II scanner, you will typically see it oscilalte back and forth, rich/lean/rich/lean as it chases stoich (lambda 1.0). These swings are nec. for cat operation (you need some O2 to burn), but they are a little sloppy. So by making my stock ECU chase a tighter signal, measured emissions actually go down (because the cat spends more time at peak efficiency). There is a tiny fuel savings, but it is so small that it is certainly not worth persuing for its own sake.

My point in all this is that there are savings to be had here, but the big Kahuna is off limits unless you don't care about emissions.
No offense but if it was easy I would have retuned my 3800 98 buick to run lean on the highway, the Emission of NoX increases but the majority of the rest of the exhaust (as found) is cleaner. Since I live in a rural area the levels of NoX my 35-52mpg car emits are likely irrelevant and will just turn into fertalizer. Now if I were in downtown LA I might worry more but evidence shows NoX may not be as much of a bad guy as the US government believes.

I would love to lean out my 010 Cobalt the rest of the way at steady state loads but finding proper tools is not all that easy or reasonably priced.

Not to mention most tools don't do lean.

Heck many Honda cars ran lean including the gen 1 insight and had EXCELLENT emissions. I don't doubt their technique would have been far superior to our pig rich and CAT approach.
  Reply With Quote
Old 07-08-2011, 10:51 PM   #30 (permalink)
Master EcoModder
 
Join Date: Jul 2009
Location: idaho
Posts: 281
Thanks: 0
Thanked 96 Times in 74 Posts
Anything out there for hacking a 1995 Buick Century V6 or 2004 Dodge Dakota 4.7L V8 to get a bit more MPG?

The Buick nudges 30 with a mix of city, highway and freeway driving. Just recently turned up 60K. Dunno what the Dakota will do yet, just bought it, needs some repair and seems to have a leaky valve on #8 so most likely the engine will need replaced. 140K miles on it.

  Reply With Quote
The Following User Says Thank You to Galane For This Useful Post:
momorris (03-09-2013)
Reply  Post New Thread


Thread Tools


Similar Threads
Thread Thread Starter Forum Replies Last Post
DIY PDR aka Dent Removal TexasCotton DIY / How-to 8 08-17-2010 01:49 PM
Calibrating the 2010 Power Bar (ECO mode) bwilson4web Instrumentation 1 08-14-2009 11:44 PM
New Eco Driving website BetsyBio Hypermiling / EcoDriver's Ed 5 08-21-2008 12:59 PM



Powered by vBulletin® Version 3.8.11
Copyright ©2000 - 2021, vBulletin Solutions Inc.
Content Relevant URLs by vBSEO 3.5.2
All content copyright EcoModder.com