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Old 16th September 2011, 18:16   #241
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

wow. it is indeed rather surprising behaviour if one depresses the clutch and brake simultaneously when at speed!
any decent driver ought to know that one can control a vehicle much better when it is in gear than when it is in neutral!
Am indeed rather unpleasantly surprised to see this incorrect practice being propounded on TBHP.
MODS - a closer watch needs to be there on such things - can be a terrible danger to a novice!

Quote:
Originally Posted by SS-Traveller View Post
Found this thread rather late, and I am to find 3+ pages full of esteemed BHPians propounding the practice of depressing both clutch and brake pedals together.

Last edited by Technocrat : 16th September 2011 at 20:46. Reason: strong language, fixed quotes
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Old 16th September 2011, 18:21   #242
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

I agree with suhaas that pressing clutch while emergency braking is not correct. This is something I have learned from experience and not by poring through manuals and youtube videos . It seems intuitive that you would want to first bring the car to a complete stop and then worry about stalling. To address anilisanil's concern, stalling will happen only at very low speeds, not before, from practical experience. As someone before pointed out you can downshift from 5th to 2nd gear without stalling. At that speed, even if you do stall it will not cause much damage in terms of losing power steering and the like.

Also, engaging clutch puts the car in neutral which is not a great idea and counter-productive if the road is sloping gently downwards etc.

However one of the things I remember being taught in driving school back in 92-93 was "Emergency mein full clutch-brake!" My Dad (who learned driving only a few years before me) used to quote this often but I was never really sure it was the right way till I started driving extensively myself.

--> Suhaas you're just 22? I thought you were my age hehe!
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Old 16th September 2011, 18:27   #243
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by SS-Traveller View Post
Found this thread rather late, and I am to find 3+ pages full of esteemed BHPians propounding the practice of depressing both clutch and brake pedals together.

I consider one of the ultimate car driver's bible to be the Institute of Advanced Motorists' Advanced driving Guide (Do you want to be a better motorist? | Do you want to be a better motorist?) (yes, I have it) - and it clearly states (as do a lot of other driver training centres) that the clutch pedal is NOT to be depressed synchronously with the brake pedal during emergency braking procedures. Those who think otherwise may want to go through the links below:
Did you notice that these links are from UK and I am sure these are still valid only to the cars/vehicles without ABS,ESP,EPS, TCS and electronics that comes with new age cars. So, yes, it is ok to use brake n clutch in succession in these cars. it is no harm doing that. whole point of pressing clutch n brake simultaneously is to avoid dividing of your concentration in crucial moments. You don't have to look for that "just before stalling point". and as I said these links still don't explain why you shouldn't press clutch with brakes in emergency.

Last edited by Suess : 16th September 2011 at 18:28.
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Old 16th September 2011, 18:30   #244
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

To clarify something about stalling, my recently acquired Ikon can do a minimum of 34kmph in fifth gear (as per the owner's manual). So if I am driving at 120kmph and need to brake, I can safely bring it down to around 40kmph before I have to use the clutch and downshift.

And while it's right to say one cannot practise and learn during an emergency, one can definitely practise and learn when there's no emergency.
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Old 16th September 2011, 19:00   #245
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by SS-Traveller View Post
...and if one finds that the ECM has such a good anti-stall mechanism as to rev up the engine when one brakes without disengaging clutch, then either the ECM needs to be replaced, or the driver's right foot is so big it presses both brake and accelerator pedal together.
Good to know I am not the only one to be intrigued about that ECM behavior.

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Originally Posted by shankar.balan View Post
MODS - a closer watch needs to be there on such things - can be a terrible danger to a novice!
Moderator did intervene at post 92, so you can't say we aren't watchful.

Quote:
Originally Posted by Suess View Post
Did you notice that these links are from UK and I am sure these are still valid only to the cars/vehicles without ABS,ESP,EPS, TCS and electronics that comes with new age cars. So, yes, it is ok to use brake n clutch in succession in these cars. it is no harm doing that. whole point of pressing clutch n brake simultaneously is to avoid dividing of your concentration in crucial moments. You don't have to look for that "just before stalling point". and as I said these links still don't explain why you shouldn't press clutch with brakes in emergency.
Do you mean to say only new age cars come with ABS & EPS? My 1991 Mercury Sable, 1998 Chevy Malibu, 2001 Acura 3.2L all had ABS and EPS, the last one even had TCS. Since ABS clearly pre-dates the Web, I am fairly sure those links have considered ABS.
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Old 16th September 2011, 19:13   #246
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Quote:
Originally Posted by shankar.balan View Post
Am indeed rather unpleasantly surprised to see this incorrect practice being propounded on TBHP.
MODS - a closer watch needs to be there on such things - can be a terrible danger to a novice!
Quote:
Originally Posted by SS-Traveller View Post
Found this thread rather late, and I am to find 3+ pages full of esteemed BHPians propounding the practice of depressing both clutch and brake pedals together.
I respect your view but that language is totally uncalled for. in emergency braking situation you need your car to save you n others, and if it is just a ball of metal with huge momentum, It's not going to help. It's not about controlling only, it is more about stopping n if stopping doesn't help, steering away to avoid obstructions. Emergency is situation gone out of control and only available tools to save you are your car n your single minded devotion.
Though OR, but can't help to say that I hope moderators will also take cognizance of language we are being on forum while I see increasing trend of calling other stupid and what else. First it was "other than BHPian" now we can use these words for follow BHPian.

Last edited by Samurai : 16th September 2011 at 19:52. Reason: original strong language removed.
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Old 16th September 2011, 19:13   #247
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by Suess View Post
Did you notice that these links are from UK and I am sure these are still valid only to the cars/vehicles without ABS,ESP,EPS, TCS and electronics that comes with new age cars.
Anything different about ABS, ESP, TCS, EBD, BA in UK cars vs. Indian cars? Are you implying that UK cars don't come with these features? Or that the IAM is an outdated organization? Oh - and EPS (Electronic Power Steering) has no role to play in the discussions going on presently.

Quote:
Originally Posted by Suess View Post
...whole point of pressing clutch n brake simultaneously is to avoid dividing of your concentration in crucial moments. You don't have to look for that "just before stalling point".
Your car + your skillset + your concentration = your crash. The final choice is yours.

Quote:
Originally Posted by Suess View Post
...and as I said these links still don't explain why you shouldn't press clutch with brakes in emergency.
You haven't looked a little closely at those links. They do explain...
Quote:
Press the brake before the clutch. If you press the clutch first the car may become unstable and difficult to control.
From this link: LD System - Driving Lesson 5 Emergency Stop
Maybe that's what the Chevy driver actually did to manage to flip his car - pressed clutch and brake together.

Last edited by SS-Traveller : 16th September 2011 at 19:28.
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Old 16th September 2011, 19:28   #248
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

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Originally Posted by Samurai View Post
Good to know I am not the only one to be intrigued about that ECM behavior.

Moderator did intervene at post 92, so you can't say we aren't watchful.

Do you mean to say only new age cars come with ABS & EPS? My 1991 Mercury Sable, 1998 Chevy Malibu, 2001 Acura 3.2L all had ABS and EPS, the last one even had TCS. Since ABS clearly pre-dates the Web, I am fairly sure those links have considered ABS.
I didn't mean to say that only new age cars come with all this electronics. what I meant that these links are from practical test point of view n the rules in transport department can be outdated. Further the first link just suggest to press clutch after brake, it doesn't say no to use clutch.
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Old 16th September 2011, 19:29   #249
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

I don't know what the big debate is about. In a speeding car, pressing the clutch first will certainly impact your ability to control the car.

Suess and others- if you must, please try this some time when the road is absolutely clear and safe.

Wisdom doesn't always lie in manuals and tutorial videos.

Anyway- what I practice works from experience, it is intuitive and most of the mods/sensible posters here seem to agree with it. So that's what it'll continue to be for me.

Edit: ECM does NOT step in to increase RPM when you downshift- that's just weird behaviour
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Old 16th September 2011, 19:40   #250
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by SS-Traveller View Post
You haven't looked a little closely at those links. They do explain...
Glanced through and came across this at http://www.findleys.co.uk/practical_...ncy_stop.html:

Quote:
Emergency Stop / Controlled Stop Gears

The speed at which the manoeuvre is usually conducted is thirty miles per hour. No matter which gear you would normally use at this speed, to perform this manoeuvre there are advantages for you to be in third gear.

If you were cruising along a main road at thirty miles per hour in fourth gear and took your foot off the gas pedal nothing much would happen because fourth is a high gear that you can go quite fast in. Therefore when you put the brakes on the engine keeps trying to push you along.
And this:

Quote:
What we are looking for in a good Emergency / Controlled Stop.

Co-Ordination.

Proper co-ordination with the brake being pressed before the clutch goes down and a firmly progressive braking action to stop the car. Keeping the steering straight and not locking the wheels.
Doesn't specifically say that the clutch should not be pressed until just before stopping, just that the clutch should be pressed after the brakes, IMHO.

Last edited by VeluM : 16th September 2011 at 19:43. Reason: And.
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Old 16th September 2011, 19:41   #251
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by SS-Traveller View Post
Anything different about ABS, ESP, TCS, EBD, BA in UK cars vs. Indian cars? Are you implying that UK cars don't come with these features? Or that the IAM is an outdated organization? Oh - and EPS (Electronic Power Steering) has no role to play in the discussions going on presently.


Your car + your skillset + your concentration = your crash. The final choice is yours.


You haven't looked a little closely at those links. They do explain...

Maybe that's what the Chevy driver actually did to manage to flip his car - pressed clutch and brake together.
No nothing different. UK cars come with these even before we get them but it doesn't mean it is reflected in test practice rules there always. That's what I meant.
and with all due respect, EPS has everything to do, it uses engine pressure which is not there if engine is stalled. I looked these links n it says no to use clutch before braking which on one has prompted till now as far as I remember.
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Old 16th September 2011, 19:42   #252
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by VeluM
Therefore when you put the brakes on the engine keeps trying to push you along.
That's because of the angular momentum of the flywheel, nothing to do with ECM.

Quote:
Originally Posted by Suess View Post
I looked these links n it says no to use clutch before braking which on one has prompted till now as far as I remember.
That means use clutch only after you have achieved the intended braking.

Read again: LD System - Driving Lesson 5 Emergency Stop

Quote:
The emergency stop
The key points of the emergency stop are as follows:
  1. Apply the footbrake quickly, but firmly, don't waste time checking the mirrors. Press the brake before the clutch. If you press the clutch first the car may become unstable and difficult to control.
  2. Keep both hands on the steering wheel until the car has stopped. When you brake hard the weight of the car is thrown forwards; this means that you need a firm grip on the steering wheel to maintain direction or correct skids.
  3. Just before the car comes to a stop press the clutch fully to the floor. Once the car is stationary secure it by applying the handbrake and selecting neutral.

Last edited by Samurai : 16th September 2011 at 19:48.
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Old 16th September 2011, 19:48   #253
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by VeluM View Post
If you were cruising along a main road at thirty miles per hour in fourth gear and took your foot off the gas pedal nothing much would happen because fourth is a high gear that you can go quite fast in. Therefore when you put the brakes on the engine keeps trying to push you along.
This is NOT while emergency braking, this is while feathering the brakes. Any manufacturer who designs an ECU which pumps enough fuel to overcome emergency braking forces are just outright stupid.
------------------------------------
Emergency braking is NOT a switch to be turned ON, and wait for your car to stop. What I mean is its not right to slam your brakes and clutch together. The time between you register the emergency and the vehicle comes to a stop is very crucial.

You need a very high presence of mind to not let the car skid, steer and achieve maximum deceleration. For this you need the engine!!.. This will also mean manually releasing and applying pressure on the brake pedal. Any bhp'n who has extensively driven a non-abs vehicle can vouch for that.

I agree this is not immediatly practical under emergency situations, but for one with enough experience, this becomes an instinct, or rather should.

Last edited by dhanushs : 16th September 2011 at 20:15.
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Old 16th September 2011, 19:59   #254
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by Suess View Post
...these links are from practical test point of view n the rules in transport department can be outdated. Further the first link just suggest to press clutch after brake, it doesn't say no to use clutch.
UK driving test rules are outdated? Ya, right...
Quote:
Originally Posted by VeluM View Post
Glanced through and came across this
Quote:
If you were cruising along a main road at thirty miles per hour in fourth gear and took your foot off the gas pedal nothing much would happen because fourth is a high gear that you can go quite fast in. Therefore when you put the brakes on the engine keeps trying to push you along.
Doesn't specifically say that the clutch should not be pressed until just before stopping, just that the clutch should be pressed after the brakes, IMHO.
So downshifting is an option, no? Downshift and release the clutch!
Quote:
Originally Posted by Suess View Post
...EPS has everything to do, it uses engine pressure which is not there if engine is stalled. I looked these links n it says no to use clutch before braking which on one has prompted till now as far as I remember.
EPS? Engine pressure? Duh?

In any case, the purpose of pressing the clutch pedal is to prevent engine stall - therefore, it is solely the driver's skill that determines the point till which he can leave the clutch well alone, and then dip the pedal to prevent engine stall. Does not mean that the clutch is pressed simultaneously with the brake during an emergency stop.
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Old 16th September 2011, 20:00   #255
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Default Re: Driver ignorant of how ABS works; Turns Chevy Captiva upside down

Quote:
Originally Posted by Samurai View Post
That's because of the angular momentum of the flywheel, nothing to do with ECM.

That means use clutch only after you have achieved the intended braking.

Read again: LD System - Driving Lesson 5 Emergency Stop
Samurai it is like we are going in circle. I read that even before it was posted here in context to similar discussion we had before on Team-BHP itself. What I m saying if you press clutch n brake simultaneously in emergency braking situation, you will have one less thing to bother about when you very close to obstacle n will be ready to steer away because engine is still running with safety, functionality of your car at your disposal.

n I can provide with a German emergency test procedure, which supports what I m saying. But link or no link, I think we should decide logically.

P.S.:I am calling it off with this. I have put my case n would like to rest my case now;-)

Last edited by Suess : 16th September 2011 at 20:02.
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