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Old 9th June 2010, 14:16   #1
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Brakes start to disengage slowly even with pedal held down

I had a funny experience with the brakes on my Ikon (1.3 Flair, 2004 model, 70K kms done). Around 2 weeks back, I got it serviced in Metro Ford, and when I took the car back, I thought that the brakes were quite tight. That is, they were engaging when I put the slightest pressure on the pedal, and didn't have to push hard. Last week, a funny thing started happening. If I pressed on the pedal softly, the brakes would engage, but then in a few seconds or so, it would again disengage. I would have to then press a little harder, and the pedal would depress further, and again brakes would engage. Again, in a few seconds it would disengage, even though I had my foot still pressed down on the pedal. This was especially noticeable when driving in traffic on an incline (car rolls back even when I had brakes pressed, causing me to press further on the pedal, or engage handbrakes). Note that on hard braking, it always engaged, and this funny thing happens only when braking gently.

I was thinking of taking it back to Metro Ford, when all of a sudden, on Monday, the problem disappeared! Does anyone know if this is cause for concern?
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Old 9th June 2010, 14:27   #2
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Quote:
Originally Posted by floyd View Post
I had a funny experience with the brakes on my Ikon (1.3 Flair, 2004 model, 70K kms done). Around 2 weeks back, I got it serviced in Metro Ford, and when I took the car back, I thought that the brakes were quite tight. That is, they were engaging when I put the slightest pressure on the pedal, and didn't have to push hard. Last week, a funny thing started happening. If I pressed on the pedal softly, the brakes would engage, but then in a few seconds or so, it would again disengage. I would have to then press a little harder, and the pedal would depress further, and again brakes would engage. Again, in a few seconds it would disengage, even though I had my foot still pressed down on the pedal. This was especially noticeable when driving in traffic on an incline (car rolls back even when I had brakes pressed, causing me to press further on the pedal, or engage handbrakes). Note that on hard braking, it always engaged, and this funny thing happens only when braking gently.

I was thinking of taking it back to Metro Ford, when all of a sudden, on Monday, the problem disappeared! Does anyone know if this is cause for concern?
Most probably air bubbles in the break line, its better to bleed them completely than to under go my plight.

Pramod
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Old 9th June 2010, 14:38   #3
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When the breaks disengage while you keep the pedal pressed, will it engage again if you release the pedal and press only that much?
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Old 9th June 2010, 14:55   #4
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When the breaks disengage while you keep the pedal pressed, will it engage again if you release the pedal and press only that much?
Yes, I think it was happening. Releasing and pressing would make it engage again.
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Old 9th June 2010, 14:59   #5
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Yes, I think it was happening. Releasing and pressing would make it engage again.
as pramod already suggested, you should bleed it completely, and make sure that there's no leak as well.
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Old 9th June 2010, 15:07   #6
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Quote:
Originally Posted by floyd View Post
Last week, a funny thing started happening. If I pressed on the pedal softly, the brakes would engage, but then in a few seconds or so, it would again disengage. I would have to then press a little harder, and the pedal would depress further, and again brakes would engage. Again, in a few seconds it would disengage, even though I had my foot still pressed down on the pedal

I strongly believe this problem is caused due to loss in hydraulic pressure used for braking.

You depress the pedal, the break pad is pressed to the disc using hydraulic pressure(break fluid), but then as soon as the pressure is created, the car is loosing it somewhere in the pressure line and hence the breaks disengage. When you press the pedal again, the process repeats, but the pressure lines are not able to maintain the pressure that's why the breaks keep disengaging.

This is usually caused by 'air bubbles' trapped and can be rectified by bleeding the pressure lines, which is a 30min task, and can be done in some local workshops(provided they are experienced/reliable). If the problem persists, you will need to take the car to Ford to check for any major issues. But as long as the break fluid level is not dropping I guess 'air bubbles' must be the culprit.

But as the problem has vanished, the bubbles must have escaped into the break fluid reservoir.

P.S- This suggestion is based upon my personal experience, experts please correct me if I'm wrong.
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Old 9th June 2010, 15:24   #7
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Originally Posted by dhanushs View Post
I strongly believe this problem is caused due to loss in hydraulic pressure used for braking.

You depress the pedal, the break pad is pressed to the disc using hydraulic pressure(break fluid), but then as soon as the pressure is created, the car is loosing it somewhere in the pressure line and hence the breaks disengage. When you press the pedal again, the process repeats, but the pressure lines are not able to maintain the pressure that's why the breaks keep disengaging.

This is usually caused by 'air bubbles' trapped and can be rectified by bleeding the pressure lines, which is a 30min task, and can be done in some local workshops(provided they are experienced/reliable). If the problem persists, you will need to take the car to Ford to check for any major issues. But as long as the break fluid level is not dropping I guess 'air bubbles' must be the culprit.

But as the problem has vanished, the bubbles must have escaped into the break fluid reservoir.

P.S- This suggestion is based upon my personal experience, experts please correct me if I'm wrong.

Spot on, after my suspension job the service center topped up break fluid, i earlier complained of break locking up but it had completely vanished so is the breaking power, I rear ended a zen couple of days back, and in the process lost some money, i was lucky that the damage was minimum, floyd i suggest you should get it fixed asap before you get to know the problem has resurfaced during an emergency situation.

Pramod
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Old 9th June 2010, 17:12   #8
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Quote:
Originally Posted by dhanushs View Post
I strongly believe this problem is caused due to loss in hydraulic pressure used for braking.
I agree with this.

Infact i would guess at some sort of internal leak in the master cylinder or something similar.

Quote:
Originally Posted by dhanushs View Post
This is usually caused by 'air bubbles' trapped...
I disagree with this!!

Airbubbles cause the hydraulic fluid to become more compressible (ie a spongy feel in the pedal). I do not think they would cause a gradual release after the brakes have been pressed.

Floyd - go get this checked ASAP!!!! If there's one thing you shouldn't take chances with its brakes!

cya
R

PS - Also check that theres no leak in the booster / vaccuum lines as that could perhaps cause something like this as well.

Last edited by Rehaan : 9th June 2010 at 17:15.
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Old 9th June 2010, 17:20   #9
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Hope you don't mind if i add a small doubt regarding my car's brake here as well. I drive a 2003 MPFI Maruti Zen. Recently I observed that once I park my car on a slope and then take start moving from there the brake seems to fail completely. If i pump it a few times it will start working normally again. And the thing is this happens only when wheels on both sides are parked at different heights. I took it to the service centre once and they told me that it was some issue with the rear brake getting jammed and that they fixed it. But every time i park in a slope and then take it the same things is observed. Can anyone throw some light on it. My car still has some warranty left and I don't think the MASS people are actually keen on replacing parts that they should be replacing and instead settling with temporary fixes.
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Old 9th June 2010, 21:19   #10
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Floyd- Don't take your brake issue lightly, get it sorted ASAP.
Probably you have air in the brake lines. Change the whole brake fluid and get the system bleed-id properly.

Nithin-Few things can cause the problem.
Air in the system
leaking servo
master cylinder seals weak
front brake hose pipe needs changing
Sticky calipers
rear brake piston needs to be inspected and adjusted
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Old 10th June 2010, 12:56   #11
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@floyd, I also drive an Ikon Flair and have noticed the same problem. I usually see this during early mornings when I have just started the car and am driving slowly. It feels as if the brake has become hard and the power-braking is not working. Even I have not faced this during hard braking.
The problem is very difficult to replicate at the workshop which makes it all the more difficult to sort out the issue
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Old 10th June 2010, 15:54   #12
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Just dropped it off at Metro Ford... they are going to do the bleeding & topping up of brake fluid. Incidentally, I was also having problems with my central locking (front left door lock was stuck, causing central locking to malfunction), so killing 2 birds with one stone.
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Old 16th June 2010, 12:05   #13
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All izz well

Just to close the thread... brakes are fine now. Metro Ford did not charge anything, since I had just done the servicing a week back.
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Old 16th June 2010, 12:16   #14
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Just to close the thread... brakes are fine now. Metro Ford did not charge anything, since I had just done the servicing a week back.
So was there a leak somewhere? What did they change?
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