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Old 28th March 2008, 12:59   #1
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Question How fast ECU learns the driving style?

Can anyone throw some light into how fast or how slow the ECU 'learns' the driving style? Is it a long term learning or very short term? Or is it a combination of both? In other words, is ECU aware of how I was driving my car say for the past few months? What if I change the driving style suddenly in a day?

I drive in different styles, and this depends on the mood. Sometimes in the economy mode (shifting within 2500 rpm) and sometimes in sporty mode (redlining, dragging from stop lights etc). So, is my ECU confused already?

And if I reset the ECU, all these learnings are lost?

I once noticed that when I drove consistently in the economy mode from a full tank to another full tank of fuel, I got really food FE. (13.7 Kmpl in a Palio 1.2 Nv. inside city) I don't know if it was the ECU or just my eco. mode driving.

Thanks in advance for the answers..!
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Old 28th March 2008, 14:10   #2
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I once had a problem where I was getting bad FE and that was due to ECU. my local mechanic told me to remove the battery terminals for about an hour or so I did remove the terminals for about a day and I guess the ECU got reset it required about a week or so to get back to normal FE but eversince the FE improved alot it never came back below 9 kmpl after that (city driving) .
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Old 28th March 2008, 15:01   #3
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My driving is mostly in Bombay within the city. Last year, I did a long drive of about 625km X 2. A lot of this was at speeds exceeding 120 kmph. By the time I entered Bombay on day 4, the ECU must have got used to my high revving drive for the past 1200 or so km. It was 8 in the evening and stop go traffic made life miserable. To make matters worse, the ECU seemed to be giving strange signals. At low speeds movement was jerky, and only at over 2000 rpm, the motion became smooth.

This lasted for a couple of days and after that the movement became more and more smooth like before.

This led me to believe that the ECU learns one's individual driving style in a couple of days time.
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Old 28th March 2008, 15:29   #4
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Does ECU learn, If yes why?

Going to office and coming back home, driving style varies a lot...
Coming home: Zip zzz zoom...screeche...Honk
Going office: ==== no screeches no honks .
I go in peak time to office and come back in off peak (20 - 30% traffic), So the morning and evening driving style is different.

What will ECU learn in this case???
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Old 28th March 2008, 15:44   #5
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An adaptive ECU! this is news to me as well. An ECU will keep track of things like knock (adjust the timing), filter (max. revs to give you), etc. but driving style ??
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Old 28th March 2008, 15:46   #6
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It will be all at sea- confused. It is probably scratching its head wondering what you are up to.

But seriously, it records information of the kind of fuel flow happening and rpm's and air temperature... I suppose it prepares some sort of a database and refers to it to pre-empt one's requirements from the engine. I wouldn't think there is any thing to worry about in this. If no patterns arise, I guess the computer chooses the average.
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Old 28th March 2008, 18:55   #7
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The ECU reads data from these sensors to determine how much fuel the engine needs and when to ignite the fuel (ignition timing)

Each of these sensors has a default value - a specific voltage or resistance (ohms). If this value is incorrect, either too high or too low for the current situation, the Check Engine Light (CEL) will light up on your instrument cluster. There are literally hundreds of error codes that the ECU can store. If they are critical to the emissions system of safety of the engine, the CEL will come on.

Now you might wonder...If the ECU has this much control over the engine, can it be modified to make the engine perform better rather than run cleaner?

Yes. Yes indeed. That is where performance ECU re-mapping comes in. A skilled programmer can dissect the inputs and outputs of the stock ECU and re program or insert a new chip with a slightly modified program that will alter the expectations of the ECU, or change the fuel delivery and ignition timing. I won't go into details here, thats for another article.

Vroom,
SK
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Old 28th March 2008, 20:27   #8
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Quote:
Originally Posted by dsskumaran View Post
The ECU reads data from these sensors to determine how much fuel the engine needs and when to ignite the fuel (ignition timing)
So ... ?
Quote:
Originally Posted by dsskumaran View Post
Each of these sensors has a default value - a specific voltage or resistance (ohms). If this value is incorrect, either too high or too low for the current situation, the Check Engine Light (CEL) will light up on your instrument cluster. There are literally hundreds of error codes that the ECU can store. If they are critical to the emissions system of safety of the engine, the CEL will come on.
Is anyone asking about CEL or MIL ?

Quote:
Originally Posted by dsskumaran View Post
Now you might wonder...If the ECU has this much control over the engine, can it be modified to make the engine perform better rather than run cleaner?

Yes. Yes indeed. That is where performance ECU re-mapping comes in. A skilled programmer can dissect the inputs and outputs of the stock ECU and re program or insert a new chip with a slightly modified program that will alter the expectations of the ECU, or change the fuel delivery and ignition timing.
Vroom,
SK

Dude no one is talking about re-mapping, read the thread topic.
You are just repeating something again and again which has been repeated milion times already in this forum.

Quote:
Originally Posted by dsskumaran View Post
I won't go into details here, thats for another article.
Please start a new article for us, we all would like to learn.

Current topic is "How fast the ECU learns your driving style"
(maybe we can reframe the question)

Last edited by chetanhanda : 28th March 2008 at 20:28.
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Old 28th March 2008, 20:31   #9
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Quote:
Originally Posted by dsskumaran View Post
The ECU reads data from these sensors to determine how much fuel the engine needs and when to ignite the fuel (ignition ......

.........

...... with a slightly modified program that will alter the expectations of the ECU, or change the fuel delivery and ignition timing. I won't go into details here, thats for another article.

Vroom,
SK
I know about all these, and these details are already available in this forum's vast knowledge base. I think you deviated from the topic here. Sad, but true.
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Old 28th March 2008, 21:16   #10
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I have my doubts about ECU's "learning" anything at all, based on the material I have read on the net.. I think most of them are probably dumb and pick up the default "map" that the manufacturer has put in the EEPROM. If there is knocking or some such thing, it'll probably switch to yet another map (again put in memory by the manufacturer).

Calling this process "learning" is a bit of a stretch.
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Old 28th March 2008, 21:42   #11
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Quote:
Originally Posted by spadival View Post
I have my doubts about ECU's "learning" anything at all, based on the material I have read on the net.. I think most of them are probably dumb and pick up the default "map" that the manufacturer has put in the EEPROM. If there is knocking or some such thing, it'll probably switch to yet another map (again put in memory by the manufacturer).

Calling this process "learning" is a bit of a stretch.
I think what learning is being referred to here is the storage of the fuelling and timing corrections according tothe driving style.
The ECU stores these values and corrects them according to your driving style, in a way "learning" the way you drive.
After a certain period the ECU does not do major corrections to these values, it simply stores them as a constant and applies the correction +/- to this constant.
The time period required for re-classifying these corrections as a constant according to driving style and not as short term fuel correction is what clevermax wants to know.

Last edited by chetanhanda : 28th March 2008 at 21:46.
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Old 28th March 2008, 22:13   #12
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Quote:
Originally Posted by chetanhanda View Post
The time period required for re-classifying these corrections as a constant according to driving style and not as short term fuel correction is what clevermax wants to know.
That's exactly it. In fact, I would have framed my question like that if I knew more about ECUs in general!
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Old 28th March 2008, 23:05   #13
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I see a vast diff in the way the OHC VTEC responds to driving style. Driving it normally reduces throttle response a bit, redline it a couple of times n you get have a very peppy engine.

Shan2nu
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Old 28th March 2008, 23:49   #14
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Quote:
Originally Posted by Shan2nu View Post
I see a vast diff in the way the OHC VTEC responds to driving style. Driving it normally reduces throttle response a bit, redline it a couple of times n you get have a very peppy engine.

Shan2nu
Exactly dude !! 100% right, I think its same for all OHCs also.
After resetting it feels pretty slow/rough because its running on default settings.Atleast what I saw ..within 10 miles my fuel trims became constant.
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Old 29th March 2008, 00:26   #15
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I think you guys just got a little crazier, i don't believe there is any artificial intelligence there in the normal ECU based engines. They are more like, push me i will run, or else i walk kinda machines. Right ?
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