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Old 18th September 2011, 16:17   #286
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by bejoy View Post
I thought the same. But had to correct myself when saw Ford Figo petrol on 3rd gear @50kmph did not stop with legs off the pedals and kept going on and on. This exercise was part of the Ford DSFL today that happened on NICE road. The road was level, may be the car might have stopped if it was uphill. Or had it been on 5th gear (overdrive), it might have stopped.
Hi Bejoy,

1) How does this disprove that costing in-gear uses less fuel than being in neutral? Could you clarify the point you're trying to make?
2) Just taking your foot off the gas will not stop the car. It will help in decelerating it faster than if you are coasting in neutral, provided you're well above idle RPM.
3) The higher the gear, the less engine braking. 5th gear would provide less engine braking than 3rd. If you were in 1st at 50km/h and left the gas, you'd slow down much quicker.
4) Engine braking is to be used as a small supplement to the actual braking - so don't expect too much from it.

cya
R

Last edited by Rehaan : 18th September 2011 at 16:19.
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Old 18th September 2011, 16:37   #287
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Hi Bejoy,

1) How does this disprove that costing in-gear uses less fuel than being in neutral? Could you clarify the point you're trying to make?

cya
R
Reehan, I did not mean to disapprove. Just was making a point that the fuel is not cut off altogether if foot is kept off accelerator.
Agree to your other points. ECU is intelligent in modern cars. Wish it was more intelligent, when it can turn on the AC compressor (if it was OFF) during an emergency braking. There by transferring some kinetic energy to the compressor.

regards,
Bejoy

Last edited by bejoy : 18th September 2011 at 16:40.
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Old 18th September 2011, 17:27   #288
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

I was out of town after posting that question on the 'safe braking with ABS by Bosch' video on page 6. And wow! A lot of discussion in the past 4 days. Thanks for the input guys.

I asked the question because I have not encountered panic braking in an ABS equipped car till now. I am about to pick up my first car with ABS & EBD. And I am a little bewildered as to how well will I make use of & react to the ABS system under a panic situation. Will I be able trust the system and stand on the pedal? After reading through each post, I think now I am 'better informed'. But, I guess after the car arrives, I am going to need some practical tests in some closed roads. At the very least, I shouldn't get surprised by my car' behavior.

Went for the Ford "Driving Skills for Life" session today morning. And the guys from Ford took us to a closed section of the Nice road for the practical tests. Wonder if I may be able to use the same.
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Old 18th September 2011, 17:38   #289
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Just was making a point that the fuel is not cut off altogether if foot is kept off accelerator.
Fuel IS cut off when you take your foot off the accelerator.

- This is assuming you are not at low / near-idle RPMs
- The car will still cruise along, especially in high gear (don't underestimate the momentum of a 1000kg car travelling at 50km/h!)
- Look at the real-time fuel efficiency gauge, it will show "0", "-", "99.9" or "infinity sign". This further proves my point.
- This is technically called as "DFCO" (Deceleration Fuel Cut Off)
- Naturally, it is dependent on other conditions too, and there are occasions when the injectors will fire occasionally - but for all practical purposes, there is no fuel going into the engine.

Quote:
Originally Posted by bejoy View Post
Wish it was more intelligent, when it can turn on the AC compressor (if it was OFF) during an emergency braking. There by transferring some kinetic energy to the compressor.
VERY interesting idea!!

This is the kind of stuff that companies like Mercedes would gladly add to their patent portfolios. Perhaps it already exists (and is probably patented).

cya
R

Last edited by Rehaan : 18th September 2011 at 17:40.
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Old 19th September 2011, 09:45   #290
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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This will be a good question to ask at Ford's Driving Skills for Life program this Sunday.
Yesterday, did anybody ask this question at the Ford event? I couldn't make it since I was driving back to Manipal.
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Old 19th September 2011, 09:54   #291
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by Rehaan View Post
Fuel IS cut off when you take your foot off the accelerator.

- This is assuming you are not at low / near-idle RPMs
- The car will still cruise along, especially in high gear (don't underestimate the momentum of a 1000kg car travelling at 50km/h!)
- Look at the real-time fuel efficiency gauge, it will show "0", "-", "99.9" or "infinity sign". This further proves my point.
- This is technically called as "DFCO" (Deceleration Fuel Cut Off)
In my Vento, it shows 85 kmpl, without any exceptions. I used to wonder why it only shows that (have mentioned it on my ownership thread as well).

NOW I know .

Amazing the things you learn without even trying, here on T-BHP!
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Old 19th September 2011, 10:11   #292
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Yesterday, did anybody ask this question at the Ford event? I couldn't make it since I was driving back to Manipal.
Not during the theory session. I dont know if anyone asked Kaushik one-on-one though.
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Old 19th September 2011, 10:41   #293
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Quote:
Originally Posted by Samurai
Yesterday, did anybody ask this question at the Ford event? I couldn't make it since I was driving back to Manipal.
I did try asking the question, however the instructor is from the sales dept at Ford and didn't know, although he did say that on a level road , in 3rd, the car will never stall; and that if there is an incline, it may. Then again he didn't know whether the 1.6 Fiesta was petrol or diesel. I didn't ask anything further.

Quote:
Originally Posted by Suess
I got my DL there in Hamburg(and in first attempt ). and i was taught to use both clutch and brake same time because a. it's easier/simpler b. stalling engine is not allowed when you are driving under any circumstances c. you are not allowed to leave steering wheel till you have finished the emergency maneuver and anyway it takes only less than a second, you don't have enough time to do a lot when you are going to hit someone/something.

I did my emergency braking test practice and exam in snowing/icy road conditions with Audi A3. lot of juddering from brake pedal but no out of control movements from car. in fact my practice was on little downward slope. it is just matter of less than a second and engine braking and all that is non-existant. further you are doing that in straight line so, no controlling of car either, just you have to hold it straight.

anyway, as noop said we are discussing here two schools and they are bound to different. but only one of them is correct for you and is one which you have practiced and are confident in.
Thanks, Suess! Funny how allowing that two schools of thought can exist is being termed dogmatic, while disallowing even the possibility of an alternate method of braking is not.
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Old 19th September 2011, 11:37   #294
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by bejoy View Post
... the fuel is not cut off altogether if foot is kept off accelerator...
Quote:
Originally Posted by Rehaan View Post
Fuel IS cut off when you take your foot off the accelerator.
Quote:
Originally Posted by noopster View Post
In my Vento, it shows 85 kmpl, without any exceptions.
Here is an entire thread of 9 pages, with some very informative posts on coasting.

http://www.team-bhp.com/forum/techni...save-fuel.html (Does coasting save fuel?)

Conclusion: When in gear, if there is no throttle input, there is NO fuel supplied by the ECU until a certain rpm, which varies for different cars. ~1500-1800 range is where ECU starts pumping in fuel.

------------------------------------

btw: "Driver ignorant of how ABS works";

We have discussed about the proper method of braking in emergency situation. Well, doesn't this incident/thread also call for the fact that, we all need to educate drivers(atleast our own) with modern safety equipments?

How many do that, and not blindly trust the sometimes all knowing drivers??

Last edited by dhanushs : 19th September 2011 at 11:42.
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Old 19th September 2011, 13:29   #295
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Having lost my car in an accident recently, I can relate to the conversation that we are having. Since I was not in the vehicle, I do not want to judge my driver who was at the wheel. But I suspect most old school drivers don't trust the brakes to avoid the collision and their first instinct is to swerve.

In my case the driver swerved and hit a median and the car is history now. Of course in the process he avoided a head-on collision with the auto-driver (who swerved suddenly to take U-turn on a highway) so I am glad there is no blood on our hands. I may never know but sometimes I wonder if the car could have been stopped in a straight line that could have avoided the collision and the damage.

I generally tend to do hard braking and don't swerve to avoid a collision. Swerving requires much more skill and it can go terribly wrong if not executed well. At least a head-on collision "after" braking is less likely to be fatal for the inside occupants. In other words: the probability of an average driver doing better than just straight line hard-braking on a busy road is low.

Last edited by androdev : 19th September 2011 at 13:33.
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Old 19th September 2011, 13:38   #296
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

^^It may not be fatal, but it is very dangerous. I spent a month in intensive care when a taxi (overtaking a bus) coming down the wrong side of a very narrow road crashed headon into me, I was on a blind turn up the bridge, which is normally always free. I braked hard as I could but the car didn't scrub off much speed. We were each at 50km/h, that's a bit like hitting a brick wall at 100 km/h.

If I had swerved the car would have gone into the bus, and there was no room to my left, that's how far down the wrong side the cab was.

As it was I had a punctured lung and a broken rib from the steering wheel, the seat belt was history and the passenger in the cab broke the windscreen and landed on the road. He didn't survive.

Seatbelts save lives. Bad drivers take them.
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Old 19th September 2011, 13:40   #297
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

"STOMP, STAY and STEER" New Rules for Driving New Vehicles

I hope this will be useful for anyone who drives an ABS equipped car read the complete article on …

Automotive Tools ?Tips ?Advice - Kelley Blue Book
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Old 19th September 2011, 14:43   #298
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

About an decade back I barely escaped an accident thanks to swerving. I was crossing a signal which was at amber, and another car followed me barely beating the red. We both were at 30mph. Right after the signal there was a congestion, and ice/slush on the road. Both of us had missed seeing it in the hurry to beat the signal. I panic braked and stopped within inches of the rear bumper of the car in front of me. The driver in rear was slower to see the congestion, she braked hard, realised she was late and then just swerved to the right and ran into the bushes. The accident was averted by swerving, that car obviously had ABS. If not for her quick swerving decision, it would have been at least 5-6 car collision with me taking the worst hit.
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Old 19th September 2011, 15:22   #299
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Samurai, are you sure the decision to swerve was deliberate, or just a reaction/reflex?

The point the OP and some others are trying to spread is we need to be ready for using the new safety features in our cars, and that means planning and practising. So is it a better strategy to brake and swerve, or to just brake or to just swerve? If we could plan it and practise it, we could actually put it to good use during an emergency.
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Old 19th September 2011, 15:36   #300
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by cranky View Post
^^It may not be fatal, but it is very dangerous. I spent a month in intensive care when a taxi (overtaking a bus) coming down the wrong side of a very narrow road crashed headon into me, I was on a blind turn up the bridge, which is normally always free. I braked hard as I could but the car didn't scrub off much speed. We were each at 50km/h, that's a bit like hitting a brick wall at 100 km/h.

If I had swerved the car would have gone into the bus, and there was no room to my left, that's how far down the wrong side the cab was.

As it was I had a punctured lung and a broken rib from the steering wheel, the seat belt was history and the passenger in the cab broke the windscreen and landed on the road. He didn't survive.

Seatbelts save lives. Bad drivers take them.
I don't mean a head-on collision :-) I mean rear-ending or you t-boning someone - in such cases hard-braking might be better thing to do than collision avoidance. Anyways - I agree - subjective and depends on the situation. I certainly don't mean head-on collision with an oncoming vehicle - that is too dangerous.
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