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Old 26th September 2009, 15:16   #1
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Strange ABS behaviour in Fiat Punto

I own an emotion pack multijet punto, about 4500km and 2 months old. This is my first abs equipped vehicle and hence the question. From whatever I know of abs it prevents the car from going into a skid, the wheels are not supposed to lock up so that you can turn while braking easily.

In the ford fusion I drove daybefore the brake pedal pounded against my foot on hard braking as it supposed to happen in abs vehicles, am I right ?
In my punto this never happens, and under hard breaking the car remains composed and straight but the tyres do squel, and sometimes quite loudly; as I said before the brake pedal never vibrates against my foot as I believe is supposed to happen.
Please provide your inputs.
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Old 26th September 2009, 16:57   #2
 
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I dont think the Brake pedal is supposed to Vibrate against your foot. Also, As long as it doesnt lock, you are all good.
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Old 26th September 2009, 17:39   #3
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Sukrit,

As far as i know, its not mandatory for a ABS equipped vehicles brake pedal to judder under heavy braking circumstances. You i think are talking of brake pedal pulsating as some people speak of in ABS cars.
Regarding tyre squeal, have braked hard from 130-140 to almost 30-40 and never heard the tyres sqeal even one bit. Maybe the full fan speed of ACC didnt allow me to hear it. Linea owners please clear my doubt too, Linea and Punto both run the 195 tyres on it (only for E pack in punto)

As long as tyres dont lock and you have complete directional control of the car even under hard braking, theres no need to worry.
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Old 26th September 2009, 17:42   #4
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Does the tire squeal when you hard brake on the Punto? That means the wheels are infact locking up, that means the ABS is not doing what it is supposed to do!

Get it checked by the A.S.S folks!
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Old 26th September 2009, 17:53   #5
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You should feel the pulse of brakes engaging and disengaging quite rapidly, in your brake pedal.

Its an indication of ABS working + it shouldnt screech. Get it checked.
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Old 26th September 2009, 18:20   #6
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We have a Scorpio Vlx. It has ABS. The brake pedal doesn't 'pulsate'. In fact, it is extraordinarily cushy. Sometimes I get scared if it would stop at all. In high speed braking it does squeal. Stop it does for sure.
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Old 26th September 2009, 18:24   #7
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The ABS is not engaging at all if you are hearing a screech. You can cross check by asking someone to observe from the road side if the wheels lock up on hard braking (even from slow speed). Please ask the service guys to prove to you that ABS is working.
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Old 26th September 2009, 18:37   #8
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Quote:
Originally Posted by DerAlte View Post
Please ask the service guys to prove to you that ABS is working.
Its as simple as that.

Also, its normal for an ABS equipped car to have a slight shudder on the pedal when braked real hard.
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Old 26th September 2009, 18:44   #9
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Check the marks on the tar after the squeal.
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Old 26th September 2009, 19:04   #10
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Quote:
Originally Posted by subscrive View Post
Check the marks on the tar after the squeal.
Precisely. Just brake hard on an empty road and see if the car is leaving skid marks. Tyre squeal does seem to mean that its locking up.
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Old 26th September 2009, 19:30   #11
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Does Punto comes with ABS light on the speedo console ? If yes then i guess ABS light should turn on during hard breaking but i am not sure.
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Old 26th September 2009, 19:51   #12
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It does squeal when you break hard even with ABS. My swift ZXi does squeal. Also, I have heard squeals even when using engine breaking (when switching from KB100 to Yamaha 100R, such confused squeals were commom)
Pulsating feeling of the brakes during breaking (do not confuse with vibration) is a good indicator of ABS.

Re-assure yourself if the ABS is working. consult your service station if you are in doubt.
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Old 26th September 2009, 23:40   #13
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I drove the fusion again, pulsates quite prominently, the punto quite def. doesn't; AND the fusion doesn't squeal at all, whatever you do. I braked as hard as I could.
Next drove the baleno, squealed very very loudly, after this drove the punto, it does squeal no doubt but it's not as loud, it's more like there's one tyre sensor that's malfunctioning or something, it seems to be from one side. Is that possible?
One more question, does abs work on all four wheels, only front/rear ?
Also thought i'd let you know, abs light goes off normally like it should 5-10 seconds after half start(just before ignition, MAR mode I think)
Thanku for ur replies guys!


Quote:
Originally Posted by Cyrus43 View Post
I dont think the Brake pedal is supposed to Vibrate against your foot. Also, As long as it doesnt lock, you are all good.
From whatever I know it's supposed t 'pulsate' which doesn't seem t be happening.

Quote:
Originally Posted by coolboy007 View Post
Sukrit,

As far as i know, its not mandatory for a ABS equipped vehicles brake pedal to judder under heavy braking circumstances. You i think are talking of brake pedal pulsating as some people speak of in ABS cars.
Regarding tyre squeal, have braked hard from 130-140 to almost 30-40 and never heard the tyres sqeal even one bit. Maybe the full fan speed of ACC didnt allow me to hear it. Linea owners please clear my doubt too, Linea and Punto both run the 195 tyres on it (only for E pack in punto)

As long as tyres dont lock and you have complete directional control of the car even under hard braking, theres no need to worry.
There's never any pulsating, thanku for the correct term; I braked hard from 80 to 30 maybe and it squealed, that's not supposed t happen because I won't have directional control then.

Quote:
Originally Posted by anachronix View Post
Does the tire squeal when you hard brake on the Punto? That means the wheels are infact locking up, that means the ABS is not doing what it is supposed to do!

Get it checked by the A.S.S folks!
Like I said, does squeal, guess I should get it checked. Thanks.

Quote:
Originally Posted by dadu View Post
You should feel the pulse of brakes engaging and disengaging quite rapidly, in your brake pedal.

Its an indication of ABS working + it shouldnt screech. Get it checked.

Quote:
Originally Posted by DerAlte View Post
The ABS is not engaging at all if you are hearing a screech. You can cross check by asking someone to observe from the road side if the wheels lock up on hard braking (even from slow speed). Please ask the service guys to prove to you that ABS is working.
i've answered this at the beginning of my post because I wanted to include a crucial point.
How will they prove it ?
Any techniques ?

Quote:
Originally Posted by abhibh View Post
Does Punto comes with ABS light on the speedo console ? If yes then i guess ABS light should turn on during hard breaking but i am not sure.
Ya it does, nope, doesn't turn on when braking hard, don't think it's supposed to.

Quote:
Originally Posted by DRC View Post
It does squeal when you break hard even with ABS. My swift ZXi does squeal. Also, I have heard squeals even when using engine breaking (when switching from KB100 to Yamaha 100R, such confused squeals were commom)
Pulsating feeling of the brakes during breaking (do not confuse with vibration) is a good indicator of ABS.

Re-assure yourself if the ABS is working. consult your service station if you are in doubt.
But if it's squealing how will you have directional control, as far as I understand it would mean atleast something isn't 'rolling' which would hinder control, right ?

Last edited by sukrit7 : 26th September 2009 at 23:52.
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Old 27th September 2009, 00:09   #14
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Quote:
Originally Posted by sukrit7 View Post
Ya it does, nope, doesn't turn on when braking hard, don't think it's supposed to.
AFAIK, the light should be on if ABS is working at that moment.
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Old 27th September 2009, 00:21   #15
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@Mclaren- well that certainly doesn't happen?
hmm, linea and punto owners, please clarify?
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