I've read several postings here about how, with time, the ECU will adapt/adjust to the driver or the car in general.

Other than varying the mixture and spark timing/intensity according to the specific fuel being burned, what does the ECU vary and how would it change according to how I drive the car?

 

 

Sometimes things are hard to search for because it's too short a term (such as ECU) or because there are SO many hits it's almost impossible to page through all of them looking for the ones that are relevant.

Which is why people ask for help on this website. And it's why some of us post helpful responses, even if the topic has been covered before.

I would appreciate links to actual threads that answer my question, in lieu of actually, you know, answering with helpful information.

 

No expert, but Throttle Position, RPM and Engine Load have a whole lot to do with it.

I've spoken with my dealer's service guy and though he's a bit vague our first talk was when I brought my FIT in for the first oil change at 9K miles w/ 40% oil life still showing and 38mpg.

I asked for a tire rotation and told him this was the first car I ever owned where I rotated the tires before first changing the oil.
He told me there was no way the car would leave the shop without an oil change.
I asked about the 9k and 40% and his reply was that I was driving the FIT the way it wanted to be driven.

Now I put those 9k miles on in six months. Right now I've got 17k miles and showing 40% oil life and that same mpg.

I'm in a rural/suburban area with little 'city' driving. I travel north to Bangor, Maine often and have traveled south to southern Florida.
My highway mpg = local mpg for the most part w/ local usually being a bit better.

If my drive cycles were stop and go w/ a heavy foot on the throttle and red-line shifts it would be a whole different story.

I drive with a light foot and that doesn't mean slow. It means I have figured out how to not apply too much throttle to get the results I want.
I also tend to shift close to 4k... Coyote taught me that, though I don't think he realizes it_

I allow the throttle lag to act as a rev match when shifting and keep 'er in as high a gear as possible. Tough to lug a FIT, hills are where you need to be careful, downshift.

I also take advantage of 'terrain'. My FIT seems to provide good mpg on those little downhill in gear coasts. I no longer coast in neutral in that the injectors shut down when in high gear and no throttle.

Hope that provides some insight - it sure works for me.

K_C_

 

Thanks.

I understand about what it learns as far as service intervals; I'm wondering what it changes as far as engine management.

 

Tech - Closed Loop This is stored as you drive, look in flash pro help to get an idea how it all works. The Fit ecu has an adaptive(learning) like all 1996 and newer cars and is capable of running some bolt ons without re-flashing. You most likely can add 10-15 percent horsepower without re-flashing the ecu. Unfortunately Flash Pro doesn't work at this time for the Fit, but the new GE8 has the same sensors as the Civic the Flash pro was made for.

Regular does not run in MBT, look at this Knock control tables.

 

Back to the original question.

I'm saying Throttle Position, RPM and Engine Load have a whole lot to do with it.Is it all based on O2 sensor data???

 

Hey K_C!

Oxygen sensor, Fuel Trims, Load, Coolant Temp, Intake Air Temp, TPS... etc. are all a part of the equation.

It records your drive cycles, and uses those to establish closed loop operation as you mentioned.

When you modify the intake/exhaust/head or boost the car and you push the Load or MAP beyond the parameters the ECU is programmed to deal with.. as in pushing it off a given table, in this case the VE table, the ECU thinks something is wrong. This can happen in open or closed loop.

The ECU does not understand you are trying to create more cylinder pressure and in an effort to save its self it scales back how much the DBW system lets you open the throttle.. when and how much fuel is delivered, when the spark is delivered etc.

All of this was covered for Shaun in two seperate threads which he chose not to read or believe.

So here we are, re-addressing the same questions. He participated in two threads already where this was outlined for him.

What Silver Bullet posted was pertinent info. I recommend anyone truly curious to read that link.. as well as every link in the 18page thread on fuel grades in the 2nd Gen Eco subforum!

The easiest way to get a feel for it is monitor fuel economy for a couple tanks while driving in a "spirited" fashion.

Then pull the battery terminals, reset the ECU and drive like a grandma for a few tanks.

The best way to do it, would be to get a scan tool or a data logger! You will learn far more and faster this way. When you have actual numbers and you know what the driving and atmospheric conditions were when the data was taken it becomes intuitive.

This is repeatable on all OBD2 vehicles. And it is for the same reason that different grades of gas respond differently.

And before anyone (I'm looking at you Shaun) tries to re-hash the octane debate, re-read this link:
FlashPro Help

Recognize it was from Hondata themselves and let that sink in for a moment before posting.

 

You need a scan gauge. Yes it based on o2 data. In close loop it try to run 14.7, but if you have e10 its 14.2. You can have an engine load of 100 percent at any rpm and depending on the gasoline you press less on the pedal. Below 3500 rpms it uses the MAF sensor and above 3500 it uses MAP or speed density. Theres correction maps for every timing,fuel,air,knock map that the ecu uses to make a new map and stores that in the RAM(random access memory). It corrects as you drive but not as fast as you think. You might have to do 4-5 full throttle passes(a few seconds) for max power. After each one the ecu adjusts up till it cant go up any more. Thats why if the weathers alway changing your mpg will not be consistent either.

It takes time for the O2 info to change so even though your car runs great until its in the long term trim, then you will see better mpg. Theres about 12 or more maps plus correction capability's.

 

Honda Fit Power Pages Results - Import Tuner Magazine Just to show the ecu does adapt to some changes before tuning is required.

DSM is right about the neg. battery terminal, but I haven't done it since my 2004 Civic.

 

I'm not talking about octane or anything else other people have posted in this thread that don't answer my question, I'm asking for polite answers to my question as to how different driving habits change how the car behaves subsequent to such driving.

Not in tuning the ECU differently or changing car parts.

 

Nowhere did anyone mention outside tuning, all of the above is done internally of its own programming. This is how all post 1996 ECUs work.

This isn't theory, this isn't guessing. That is what is going on. The same rules and operations apply to fuel grades, as they alter how the ECU responds to your different driving demands.

Do we need to break out the crayons next?

Drive the car hard, it gives you more fuel, more spark advance and quicker DBW response.

Baby it and you don't reach the load cells where it needs to do any of these things.

It's really pretty simple. By discussing what happens when the engine is modded from stock or differenet fuels are use, we are trying to illustrate how the ECU adjusts under different situations. I am sorry you are too thick or obstinate to understand this.

You can ask politely, but if you don't want to learn why bother?

We are spelling it out for you and you are pretending we havent answered your questions. What more can we do besides laugh and move on?

Your questions ARE in fact being answered, you just don't get it. I and others have gone to great lengths trying to break it down for you in other threads. But still, you don't understand the basics, so how would you "get" something so much more complex as adaptive ECUs tend to be?

 

We're lucky to have people who "share knowledge politely".

 

More "sharing knowledge politely" I see.

 

Besides recommending a battery swap any ape with a tape measure could figure out what have you shared?

I have helped in bringing the first USDM GE turbo to reality.. how about you?

I help people via PM constantly, how about you?

I help people in the real world modify, tune and fix their cars.. why should I bother being nice to those who can't do the simple stuff for themselves and post stupid threads like this?

He has already had the run down in two seperate threads. I offered to walk him through a few different sets of tuning freeware, demo videos, I offered to send him text books, .pdfs, etc.

He is not interested. He is looking for quick yes/no up/down black/white answers.

This is not how ECUs work. He still refuses to learn the basics, and so here we are.

With out the fundamentals, this will just continue to go in circles.

Call me an A$$, I don't care, at least I know WTF I am talking about here. Anyone who has sought my help directly gets the utmost in polite response. I genuinely enjoy helping those who are actively seeking to learn.

This is just ****ing lazy. The resources were shared, other options offered by myself and others. He did not seize the opportunities.

 

Let me try to explain what I have learned, and what I am asking, without any counterproductive name-calling nor responding to irrelevant accusations.


I understand that every car is different, and that over miles and miles of driving the ECU learns how various settings affect the car and it adjusts itself accordingly.

I understand that when you step harder on the gas you get more power than when you don't (obviously). With me so far?

What I am asking is:
two scenarios:
1. Drive the new car like a maniac for 1000 miles.
vs.
2. Drive the new car gently for 1000 miles.

I understand that in gentle driving it'll have less data to work with when it comes to full throttle, for example. So the programming the ECU learns will be different and maybe less complete.

BUT- once it's driven through enough data points- full-throttle, etc. will the ECUs in the above two cars have different data that will cause the car to react differently under the same future driving conditions?

And if so- what difference will the settings have? For example, will the car driven gently tend NOT to respond with as much power when it IS floored? Because the car 'learns' that the driver isn't so interested in power?

 

Oh, two more things that are off-topic but were addressed irrelevantly by others in this thread so I'll respond:

1. I helped a guy who had battery questions (not about measuring, by the way). Maybe the questions were too simple or the solutions too obvious for some people here with lots of expertise, but I answered his questions and he appreciated it. That's what this forum is for, isn't it?

2. I think I proved my usefulness in my response on this thread:
https://www.fitfreak.net/forums/gene...-ticket-3.html

 

Alright this is a good start in the right direction I apologize for having to take it to that level.


For the first part of your question.. for lets say any given 15 minutes of running time, you will always yield the same "volume" of data. Let says 1 megabyte of run time is 15 minutes worth.

It is just different in what it contains.

For instance if we pretend everything in the ECU is binary (lets over simplify) and say that all fast driving produces "1's" and all slow driving produces "0's"

15 minutes of 1's will fill the same 1megabyte as 15 minutes of 0's

Likewise if that 15 minutes is mixed driving, you will still still have 1 megabyte worth of 1's and 0's. Make sense?

So, with that established we can answer the second portion:

Yes the two cars will react differently. The ECU has adapted to those styles of driving, on a given fuel in a given environment. So when you hit the gas in either car, all it will have to go on is what situations it has already seen and recorded.

But if it finds it can get away with more aggresive settings, like the ECU in the slow car would discover, it will gradually find the limits and adjust to be more aggressive.

Likewise if you start babying the fast car, the ECU will still initially respond with to the effect of what the previously collected fast data would suggest it should do, IE. be fast and aggressive.

But if over time you keep babying the car, even though it "knows" what it can get away with, it sees that you aren't asking it to do this, so it will just not use the settings available for when being driven hard.

The ECU is constantly relearning and re-recording your drive cycles, and if you keep driving like a grandma it will eventually only have the slow data available. Then if you change your driving style back to aggressive it has to relearn.

It just so happens that aggressive driving moves through drive cycles quicker, so a return to grandma "slow" settings takes longer. This is why I recommended the "drive fast, reset ecu, drive slow" test earlier. So you don't have to wait weeks to potentially months to watch the ECU get less aggressive again.

Well a "fast" tune with only 1's having been recorded you will get faster throttle movement from the DBW. You will get more peak timing under WOT, and the ECU will less hesitantly produce more fuel and inject it earlier to take advantage of more swept area and let the flame front propagate for longer which produces more torque.

The "slow" tune can be the same as the "fast" tune counterintuitively. You just won't reach the aggressive tables and cells used in the "fast" tune.

Now one of the concepts I have been getting most frustrated about is that the data used for the fast and slow tunes are only going to be as aggressive as the fuel allows.

So your fast tune on 87 will be different than your fast tune on 93.

Likewise, your slow tune and thus your fuel economy will vary dependent on fuel too.

This is where things get very complicated, as is evident in the other two threads. Silver Bullets links would help demonstrate this with relation to MBT and Fuel Economy on a given fuel.

Check this one out:
http://www.hondata.com/help/flashpro...rol_tables.htm

 

Think about it. Since probably everything possible has been covered at least a dozen times, if everyone that came on this forum did a thorough search to find their answers there would end up being no new threads and consequently no reason to come here. Not really too smart!

 

Are you suggesting no one ever tries new things here? Or that unique problems don't arise?

No one has anything to sell?

There will still be plenty of people coming here, I assure you.

I will guarantee you there is a hell of a lot that hasn't been covered on these forums.

In posting a million repetitive threads you are actively making it harder to search for what good information is available. Even then you still get morons who've put a cone filter and JB welded a fart can to the car pretending to be automotive engineers and yet further obfuscating what data is available on this forum with unfounded inexperienced and uneducated opinions taking the place of fact.

Encouraging it is part of the problem. You are diluting the usefulness of the forum in doing this, and making it more of a turn off to people who aren't into decals and other BS.

There are a lot of posters who do not share anything anymore because of this. Recently several have attested to this fact. I have been lurking here for years, and many people like "explosiv potato" and others don't bother.

Some of us are trying to rehab this clusterf*ck. Even if it means dragging some people kicking and screaming into the light. Think Platos' Allegory of the Cave.