[Traveller Nayak]

Team: another brake related query where I need your help.

Vehicle: Toyota Fortuner AT. July 2013.

Done: 17000 kilometers. City and on good highways

Issue: feeling of ‘skidding / loss of traction’ when water is thrown on the front tyres

I have noticed on each of the days the vehicle cleaner has thrown water on the front tyres, for the first 2 or 3 brake usage I get a feeling of ‘skidding / loss of traction’ accompanied with sound. This has not happened on the main road. I have experienced this when I exit from my parking slot and go towards the apartment gate. A distance of about 100 meters, which involves 3-4 turns and thereby brake being applied. Because the vehicle is within the apartment complex, the vehicle speed is at best 10 or 15 kmph or the minimum that is required to keep the vehicle moving forward.

If water on the tyre is an issue, then the same issue will come up if the vehicle passes through standstill water/ streams. I am planning a Leh trip in September, 2014.

Is there anything wrong with the brakes? Do I need to take any action / precaution?

Thanks as awlays.

[Aroy]

Originally Posted by Traveller Nayak

Team: another brake related query where I need your help.

Vehicle: Toyota Fortuner AT. July 2013.

Done: 17000 kilometers. City and on good highways

Issue: feeling of ‘skidding / loss of traction’ when water is thrown on the front tyres

I have noticed on each of the days the vehicle cleaner has thrown water on the front tyres, for the first 2 or 3 brake usage I get a feeling of ‘skidding / loss of traction’ accompanied with sound. This has not happened on the main road. I have experienced this when I exit from my parking slot and go towards the apartment gate. A distance of about 100 meters, which involves 3-4 turns and thereby brake being applied. Because the vehicle is within the apartment complex, the vehicle speed is at best 10 or 15 kmph or the minimum that is required to keep the vehicle moving forward.

If water on the tyre is an issue, then the same issue will come up if the vehicle passes through standstill water/ streams. I am planning a Leh trip in September, 2014.

Is there anything wrong with the brakes? Do I need to take any action / precaution?

Thanks as awlays.

Actually the tyres should grip better as the surface is moist and grip on concrete perfect. You will also get tyre squealing noise as you get some times on polished floors. In case the path is not concrete but gravel, then the car will slip whether the tyres are wet or not, but no squealing noise. Nothing to be alarmed at.

[a4anurag]

Originally Posted by Traveller Nayak

I have noticed on each of the days the vehicle cleaner has thrown water on the front tyres, for the first 2 or 3 brake usage I get a feeling of skidding / loss of traction accompanied with sound.

Just my thought is the phenomena Aqua Planning occurring to the car when you drive out wet?

Another reason is once the car is washed the brake pads + rotors + brake disc are all wet/moist so the braking is not effective causing it to slip due to moisture (pads not able to grip the disc plate). Once the brakes heat up, it is normal. It is advised to heat up the brakes and only then drive at regular speeds till then be slow. You'll have to keep pumping the brakes continuously till it is almost hot to get rid of moisture.

I follow this is practice regularly whenever the car is washed.

Anurag.

[Traveller Nayak]

Originally Posted by a4anurag

Just my thought is the phenomena Aqua Planning occurring to the car when you drive out wet?

This is correct. Thanks for the guidance. I will follow this henceforth.

[hemanth.anand]

Originally Posted by DCEite

I too have a weird problem with braking on Spark car.

The issue is that suppose i am in a gear (lets say 2nd), and then without downshifting or shifting to neutral, i brake. All is well. Now i release brake pedal and let the car continue without giving accelerator input, and again brake 2-3 times, then after the 3rd or 4th attempt - the braking has no effect. As if the engine is shut off and it keeps moving in the momemtum without stopping. Sometimes it gets scary in stop and go traffic, where i don't use accelerater but continue braking 2-3 times in same gear without operating the accelerator.

Anyone faced similar issue?

I have faced this exact issue in my 2010 Punto 1.2. Scary indeed!
This was only an issue in bumper-bumper traffic and not on the Highways (Which is quite obvious as the accelerator pedal would always be depressed during highway driving).
I had adjusted my driving style accordingly - just to keep my brakes at thier best, I used to revv the engine in between the braking intervals.

In fact all Punto 1.2 owners had complained of this issue from the beginning.
Last month Fiat called all 1.2 Puntos and flashed updated software to correct this issue (note that mine is a 2010 Punto).
This update actually tweaks the brake servo pressure.

After getting it updated, I've not experienced the problem in around 400Kms that I've driven in city.
After the updation, the service centre guys had forgotten the print-out copy of the presentation in the glovebox which shows the steps to update.
It had some details of the update...A picture of it is attached below.

[msdivy]

I had given my car to Magnum Honda. The service engineer did a test drive & reported that the brakes have gone weak. On further investigation, he said the disc rotor has rusted & there was scoring on the disc. Brake pads were fine. So the front 2 disc were replaced and brake were bled. Now the braking is fantastic.

Old disc


New disc


Price

[joybhowmik]

Originally Posted by a4anurag

Just my thought is the phenomena Aqua Planning occurring to the car when you drive out wet?

Originally Posted by Traveller Nayak

This is correct.

Aqua Planing - or Hydroplaning requires much more water than a couple of buckets thrown on a wheel. It occurs when there is significant amount of water beneath all wheels, such that the vehicle loses all traction with the road surface.
During Aqua Planing, the vehicle can actually pivot /rotate 180 degress C.G., to face the other way to its main direction of travel.
Aqua Planing happens, when you drive over a long puddle , or a rivulet or other water body, where the water depth is significant compared with the weight of the vehicle (there are other factors that influence this as well).

What you have described , is a case of the tyres and brakes made wet due to the water spray. You will lose some traction due to the lubricating action of water on the surface - but not all traction. More importantly, you will not lose complete control , and you will regain what you have lost as heat builds up (tyres and brakes get heated), and water is shed from the surface due to rotation.

See this link for more information on Aqua Planing: http://en.wikipedia.org/wiki/Aquaplaning

[MMV]

Team,

Need inputs/guidance on the sudden loss of braking power experienced with my car.

Car: Etios GSP
Road Condition - Dry (no effect of rain)

Yesterday, as I was slowly moving in a traffic signal (accelerator was not pressed) the signal turned red and had to stop. To my horror I got no response after pressing the brake, tried once again and quickly engaged the hand brakes to stop the car. But by the time my car just touched the car in front (soft impact and no damage). I was perplexed and shocked and the car driver ahead turned back. (but as the traffic was long he also went ahead without saying anything)

As the signal went green, I proceeded cautiously checking my brakes few times and completed my trip (though with added caution). The braking was normal barring that stray incident. I spoke to my brother on this and he said he had also experienced loss of braking power on couple of occasions (different car models) and its due to either loss of power delivery from engine or ABS malfunction.

Sometimes while idling at traffic islands I had felt the engine grumble reducing indicating a fall in rpm levels (my car does not have an rpm indicator to verify) but as this had happened many times and had not resulted in any malfunction I had ignored it till now.

I am planning to get my car checked at the dealer soon (prior to any long trips) but want to know the reason for this bizarre incident, is it a rare issue with power assisted braking or something more. Also in case others have felt same issue with their cars please provide your insights.

Best,

[interc00led]

Originally Posted by MMV

Team,

Need inputs/guidance on the sudden loss of braking power experienced with my car.

Car: Etios GSP
Road Condition - Dry (no effect of rain)

Yesterday, as I was slowly moving in a traffic signal (accelerator was not pressed) the signal turned red and had to stop. To my horror I got no response after pressing the brake, tried once again and quickly engaged the hand brakes to stop the car. But by the time my car just touched the car in front (soft impact and no damage).

Since your car is powered by a petrol engine and you mentioned that the idling rpm has fluctuated, I think there is a vacuum leak somewhere. The brake booster needs vacuum to reduce the braking effort but then the brakes wouldn't fail completely- only the pedal would become hard.

Get the vacuum and brake lines inspected as soon as possible.

[honeybee]

Check if the brake fluid is leaking, especially from the rear drum cylinders, but also from the master and slave and front discs. A loss of fluid under pressure may take away your braking power.

[Aroy]

This is most probably brake fluid leak, air bubble in the fluid or vacuum leak.
. Get a competent mechanic to "bleed" the brake lines.
. Check the Vacuum lines for any leak.

I remember that when we had the Esteem MPFI, at times the brake would go absolutely soft when the engine was off - vacuum problem.

[MMV]

Thank you for your valuable inputs.

Had a thorough check done for my vehicle from Toyota (Shinrai Toyota - Service Center) and found no technical issues. They did a check of brake lines, booster, checked for fluid leakage and vacuum leak. Also throttle body and spark plug were checked for possible reasons for rpm drop or issues in idling.

I personally drove the vehicle with the technical staff and found no recurrence of the braking power loss at near zero speeds. The explanation given by the technical staff was that it may have occurred as a rare coincidence with the engine momentarily turning off (or rather was about to turn off) resulting in power loss. Also the rpm fluctuation (noticed by way of change in engine grumbling noise) was on account of compressor switching off or on.

Anyways I was satisfied with the alacrity and swift response provided by Toyota on this issue. I had logged a grievance at their portal and immediately the query was attended by my dealer.

Regards,