Sunday, March 15, 2015

Adpaptive ECU learning

Adaptation in the ECU comes in 2 parts. The first is the ODB2/EOBD adaptation for emission control.
This is fine tweaking of of the maps to counteract wear and tear, dirty injectors and air leaks.
For example, the ECU will have a programmed target lambda on a  car. If the fuel filter becomes clogged, the car will start to run a little lean.

Short term adaptation is carried out almost immediately from feedback from the lambda sensor.
It's worth noting that narrowband lambdas can only measure excess oxygen, so rich conditions can't be measured apart from the fact there is no oxygen left, so it isn't able to know how rich the mix is. Likewise, the narrow range won't show too much details on how lean due to the response of the sensor.

Electronic throttle control systems may seem a little silly. After all, if a mechanical throttle control system works, why make it more complicated?

While it's true that electronic throttle control adds complications, it also adds a number of benefits. The first is decreased maintenance. Mechanical throttle systems, because they are made up of a lot of moving parts, are subject to a lot of wear. Over the life of the car, the various components can wear out. By comparison, an electronic throttle control system has comparatively few moving parts -- it sends its signals by electric impulse, not moving parts. That reduces wear and the amount of maintenance needed on the system.

In this age of electronic throttles, even the throttle usage is learned by the ECU, a quick two to three taps of the accelerator will let ECU know that car needs to better response, so ECU will treat each position of accelerator with little added % of throttle value from the base map. Usually it will be max of about 10%.

I am not sure but I feel even it slightly advances the start of the injection in the timing cycle.

The reactivity of the sensor isn't too quick either, so after about 3000-4000 rpm it can't react quick enough to provide anything useful so the car operates in the dark based on the programmed info.

From the info collected from the short term adaptation (below 3500-ish rpm) the car builds a picture of the general state of play.
If it has been adding extra fuel through the short term trim, it then gets added to a long term bank.

Sources
Bergholdt, Brad. "Under the Hood: Electronic Throttle Control is Complicated, But Precise." McClatchy-Tribune Information Services. February 26, 2010. [March 8, 2010].http://dailyme.com/story/2010022600004464/hood-electronic-throttle-control-complicated-precise.html
Lienert, Anita. "Toyota's Electronic Throttle Control and Electromagnetic Interference Testing Presentation." February 23, 2010. [March 8, 2010].http://www.insideline.com/toyota/toyota-throttle-control-and-electromagnetic-interference-testing-presentation.html
O'Donnell, Jayne. "Could electronics be what's causing runaway cars?" USA Today. February 23, 2010. [March 8, 2010].http://www.usatoday.com/tech/news/2010-02-23-Electromagnetic23_CV_N.htm
Pico Technology. "Electronic Throttle Control." Pico Technology. [March 9, 2010]http://www.picoauto.com/applications/electronic-throttle-control.html
Rhee, Joseph. "Toyota Slams Sudden Acceleration Research of Auto Expert as Unrealistic." ABC News. March 8, 2010. [March 8, 2010].http://abcnews.go.com/Blotter/RunawayToyotas/toyota-slams-sudden-acceleration-research-auto-expert-unrealistic/story?id=10042858&page=1
Ross, Brian. Expert Recreates Sudden Acceleration in Toyota." March 4, 2010. [March 8, 2010].http://abcnews.go.com/Blotter/video/testing-toyota-9914148?tab=9482930&section=1206853&playlist=1363488
Thomas, Ken and Stephen Manning. "Toyota disputes critic who blames electronics." The Associated Press. March 8, 2010. [March 8, 2010].http://www.google.com/hostednews/ap/article/ALeqM5iNwJcVe09iBDYjmKOaeF4IU9vGRwD9EAOO0O0
Toyota. "Comprehensive Analysis Raises Concerns About Gilbert Congressional Testimony, ABC News Segment." Toyota. March 8, 2010 [March 8, 2010].http://pressroom.toyota.com/pr/tms/electronic-throttle-control-154300.aspx

Monday, February 16, 2015

How to get best out of your ride



As of the time I am writing this blog , I know  there is post on Team BHP about how to maintain your car in top shape but, this is lot different than that article.

How ?

This blog is about over all maintenance of the car but more specifically the running parts like engine. Add to that lubricants, remaps, most importantly a proper skilled mechanic is a basic requirement to do anything.

You will need a mechanic, who is ready to step out of conventional thought process and goes beyond your expectations.

My requirement was very simple.I wanted to get a smooth/refined ,powerful and yet stylish car. You will know how difficult it is to get all of my requirement in one car.

May be first generation i20 met my above requirements but it was expensive and no match for Punto in handling and ride quality.

Or a Honda city VTEC would have satisfied to an extent but I might have ended up changing shock absorbers to get good handling :-),not sure what I would have done to get the solidity offered by FIAT.

Honda i-Dtec disappointed me as engine is more noisier to an extent I would hate to drive it again.

After all I am not a new car buyer who would buy a car based on looks of the dash board.

I got only the last part that was "style" part of my requirement right, as most of people I too believed the quote " car will become smooth after few thousand kms "

Why obsession with smoothness or refinement?

Smooth engine would have less friction between moving parts, there by delivering either power or fuel efficiency depending on how you want use it.



To start with , I own a kind of not so popular car called Grande Punto or "point"  in Italian. This post is not about why I bought such a unpopular or junk car as per some of your opinion.




Post is about what are things I did to the car,even still a month to go for 5 years of ownership, I am still in love with it.
My car bought in year  2010 doesn't have the O2 sensor, so essentially it is open loop fuel injected CRDI car with 5 injections per cycle!!

Some time towards later part of 2010, Punto started to have 1.3 MJD engine with O2 sensor Argah... yes those cars are little more refined.




1.3 MJD is very popular engine although car is not. in India Maruti Suzuki uses FIAT engine in its diesel cars and as well as TATA in some of its popular cars that sell in thousands!!


Even GM has the same engine in few of it's cars, again I am diluting the topic , let us get back..

My car did not drive or sound as good as Suzuki or TATA with same engine, it was even slower too. Most of the times car felt like being driven with 15 year old generator engine as my friend Imran puts it across.

Few of my friends who bought car along with me cursed FIAT and moved on to other brands, FIAT lost few customers due to this but FIAT is like elephant they don't acknowledge a pin prick.

I have enough friends who ridiculed my decision to buy a Punto  rather than follow the herd and some of the  FIAT friends who questioned the engine option I chose,not knowing there was no 90HP in march of year 2010.Tjet Punto may or may not be a reality in 2015.

For me a car has to give atleast 13-14 kms in city and 21+ on highway, Punto betters these numbers by 10-15% , even after spirited drive car still reads good average FE, so I was not wrong with my decision to buy Punto but drivability and NVH(Noise,vibration and harshness) were fly in the ointment.

I understand  what a good oil can do for a car, so moved away from FIAT's selenia WR 5W-40, which is semi synthetic and FIAT wanted me to run on such oil for 15000 kms!!

If you are satisfied with FASS oil and how your car runs with it,please save your time by not reading further.

I am/was more concerned with how many microns of bore is going to be saved from the friction induced wear with fully synthetic oil.

I switched to one of the best brands of oil Mobil 1 Delvac which was API E5/E7 rated in 2011(yes I ditched the warranty),if you need to know more about engine oil ratings google for "engine oil bible".

Refinement did increase a bit with oil that costs twice as much as Selenia!! but no where near to what Swift or Vista was offering with inferior lubrication, even Punto's with O2 sensors were better.

Choice was to sell the car and go for new Punto 90 HP which comes with O2 sensor and enjoy.

Easy decision,period ? 

No.An enthusiast and an economist in me was not ready to accept that.

Fully synthetic oil alone did not fulfill the need. Only difference was at high RPMs. But car was usual clattery and felt rough in city speeds.

Now the option was to go for additional friction reducers by the way of engine oil additives.

I tried different additives and oil brands, 3M, Bhardhal,Wynn,STP,Abro and finally OWS220, I will come to OWS part little later.

3M went into my car at around 250 kms on ODO!!

All the other additives tried were good for some time but did not transform my car's engine to buttery smooth engine.But better than just synthetic oil alone.

 I might have done 5-6 engine oil changes between 26K Kms to 42K kms :-). I stuck to Abro for quite some time until I switched over to OWS.


Each oil change I used to supervise myself, make sure oil filter is primed before install, I must thank my mechanic and friend Harish Naik of pride cars for putting up with all the crazy things I was trying.

Got EGR,Intercooler,Sensors cleaned twice along with radiator flush and coolant changes.This is a must for MJD engine as sludge blocks the air passage in intake manifold and car will under perform.

Meanwhile I got the car's doors dampened to reduce the outside noise.Happy that outside noise is less but engine noise was more noticed afterthat.



Between, I am a frequent traveler , so I used to drive a lot on the week ends, highway drive used to feel good and I used to comment about Punto as good "highway car" in time pass discussions at office or forums.

I never understood why a car feels so good on highway but feel like a old DI engine in city!! Always used to crib about refinement in my friends car's :-)

Later part of 2011, I got my car remapped by TOT folks( Tune-O-Tronics) , car became better at drivability and power but still I was missing refinement , car would feel very refined when Siddarth was there and become very much like tractor later( more so when some one resets the ECU by disconnecting the battery), I got different maps from TOT but to only get disappointed later.

Fact,it was not TOT's problem but my inability to tell them what I wanted.Sid of TOT became hard to reach due to some personal issue,so just lived with what I had.

Some time in year 2014, I got a bottle of OWS 220 and mixed it with 2.9 lts of Mobile 1 delvac, I had no expectation with it but just wanted to try.

About 50 kms to 500 Kms, car's refinement started improving but in city driving conditions,when you are driving less than 2000 rpm diesel clutter was still there also lethargic response from engine.

(OWS 220 was like water thin rather than thick 90w oil like additives I used earlier.)

This situation baffled me, a great sounding,powerful and refined car at highway speeds doesn't feel good in city that too after all exotic oils with additives!!

Two major accidents that happened in meanwhile , that made me to stick with the car as it is built like a tank. 
I would not like go further on this point of safety. As I feel safety is directly related to money you are ready to spend.

I am no FIAT fanboy as such.But I like their cars for sheer brilliance and road presence.

Then after a year of thinking and driving cars remapped by Wolfmoto  folks, I decided to give a try, this was not for raw power or torque but quite and refined engine.

Many a times, when ever I drove Rajan's or Gopi's Tjet I felt , it is right choice for me. But I had to make sure 7.3 lakhs I spent on my car was not going waste.

Got stock plus 4 maps, but due to small turbo and absence of O2 sensor ,car smoked heavily.

I upped the turbo boost by adjusting waste gate close to 2 bar from 1.6 bar.Yes you can change the the wastegate opening with respect to boost mechanically. Car showed strong push in the turbo band and smoke reduced little bit.

For all who own diesel car, don't be alarmed by black smoke, there is bound to be little bit of it.During hard acceleration there will be cloud of it.

What you need to concerned with is white smoke or blue smoke, both of them point to an issue with engine.

I must appreciate Harish of Pride cars in helping me to remove the turbocharger and adjust the waste gate multiple times until I was satisfied.

Now after so much of circus without knowing the outcome of each experiment, the refinement was there sometimes, when I was frequently driving between city and highway drive but only city drive car would still feel little lethargic but if you give more gas they it would be okay or bearable.

A road dyno test done in second gear gave 83HP at wheels!! At crank it may be 92 HP.

Started adding 2T oil of about .1% to fuel, it made some difference so decided to continue the practice.

(Actual ratio is 45 ml for 45 ltrs of Diesel,it can go to 1000:1 or 500:1)

2T oil quietens the intake valve noise also lubricates compression ring to an event,there will be noticeable difference with 15-50 kms drive.

Please read the below note on 2T oils before you jump into using it.

(In two-stroke oil we get 4 different quality ratings, which are based on the JASO (Japanese Automotive Standards Org.) scale:


JASO-FA very basic single grade SAE30 or SAE40 based 2-stroke oil (premix only)

JASO-FB Used for most premix industrial 2-stroke engines and scooters

JASO-FC "Low ash burn" used for separate oil injection and most outboard motors. this oil can be mineral or part synthetic

JASO-FD This is fully synthetic 2-stroke oil for racing engines. It is not suitable for mixing with diesel, because a) too expensive and b) not compatible with cats and particle filters.


Now in order to provide better lubrication but at the same time also better power delivery from the engines, the ideal solution seems to be to add 2-stroke oil (see above) in a mixing ratio of 1:500 or 1:1000 
 i.e. 1 or 2 ml per liter of diesel.
This will increase the cetane rating by 3-5 points and will provide the following benefits:

1. Much better and more complete combustion (lower EGT)

2. Self cleaning of engine internals, as JASO-FC compliant 2-stroke oil burns cleaner and better than diesel. Due to this there is also about a 3-5% gain in fuel economy.

3. Sufficient lubrication of high pressure components in the diesel injection system.

4. Much quieter starting in the morning and smoother running)


Got in touch with Rajiv Chandran again and explained him my requirement clearly, he gracefully helped by writing few test maps before I settled for one two weeks back.

Rajiv's work was brilliant, he gave me the tune which I liked the most.I am loving the way car accelerates even now.

Car was refined but lethargic/cluttery response continued for few more days, I came to a conclusion that there is some thing else needs to be done to get what I was trying so hard with money and time.My wife used to think what's wrong with me.

My wife wanted to have food in restaurant so we decided to drive to a restaurant inside Iskon Temple.

I drove to "the higher taste" hotel on one afternoon, car was making lot of noise after 2400 RPM, and feeling like hell with diesel clutter.

You can imagine my plight ,I might have spent over  lakh and half on oils ,additives,clearcoat, tires and remap alone.

After having lunch, I drove the car after tapping the accelerator 2 or 3 times until tacometer showed 2500 RPM.

It was purely  some instinct rather than any brilliance of mine :-),may be I forgot to engage the reverse gear and tapped accelerator to get the car moving.

Came out of Iskon temple parking, and car was very silent and refined!! acceleration was quick without the associated free package of Noise and clatter!!

After which , I have been following the same procedure but RPM touching  just 1500-1700 at max. Car drives like  petrol car with quick and very refined engine.

Viola! Found a secret switch to Nirvana.Up to 90 KMPH car drives like a petrol car with respect to Noise or vibration, post which engine roars.

A car should do a "purr" in lower RPM band and "roar" in higher RPM but without vibrations or harshness.This is the quote of Somender Singh sir, I respect him a lot for what he has achieved.

By all the above stuff and two tapping procedure,I was able to connect to the soul of the car and get what I was looking for from the car.

Now I have a Honda's refinement in FIAT.Those who don't believe me can come and do a TD of my car.

I feel this adaptive ECU learning is either disabled or throttle usage is ignored in TATA and Maruti cars that use FIAT engines.

That might be the reason why all half knowledge auto reviewers claim Maruti has tuned the car better.

So it took me 5 years to get what I desired.Car feels better.

You will need a good quality oil+additives and remap to get best of car like Punto.


NVH levels are on par if not better than other cars that use the same engine.

Delivering good FE,refined engine and yet powerful.


Afterall great cars are the ones you like not the one rest of the world likes.


It takes big R&D $$$$ for car makers but I am lucky to do so in less than $2000.