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View Full Version : Weird issue during braking


xtremesniper
04-28-2009, 05:10 AM
I'm not sure if this is really an issue, but I thought I'd try to explain it on here to see if I'm the only one with it or not.

Basically, there are times when I approach a stop light or a speed hump where I'll either gently press on the brakes to slow down from lets say 40 to 20km/h, or just to a full stop (in the case of a stop light), or I'll let the car glide to a slower speed (and sometimes the Yaris does its own "engine braking"). During this slow down, sometimes it kind of feels like a certain part of the brake pad is tighter than the other. That's the best way to explain it I think, because you'll feel like there's a slight/subtle tapping of the brake that I'm not actually doing every half second (possibly every revolution of the wheel). It seems to only happen when slowing down from an already fairly slow speed, which is why I only feel it sometimes because I'm usually driving on roads with a higher speed limit.

Anyone know what I'm talking about? Should I go in to get this checked out?

mojoyaris
05-11-2009, 01:00 AM
It could be your brakes pads are unevenly worn or your rotors need resurfacing???

Loren
05-11-2009, 02:22 AM
Automatic transmission, right?

1NZYaris1
05-11-2009, 04:26 AM
Don't the RS Yaris over there have ABS, with Brake assist , :iono:
In New Zealand they do , that would be your answer :thumbsup:

808_Yaris
05-11-2009, 04:31 AM
for US cars. when braking going down the hill, the brake does to brake on it's own too. it may be the ABS kicking in. i don't think it should be a problem for you.

Tamago
05-11-2009, 09:18 AM
for US cars. when braking going down the hill, the brake does to brake on it's own too. it may be the ABS kicking in. i don't think it should be a problem for you.

there's no way that the ABS is actuating automatically while going down a hill lol..

808_Yaris
05-11-2009, 12:21 PM
Maybe higher rpms when rolling down the hill slows down the car while breaking ?

xtremesniper
05-11-2009, 12:53 PM
It could be your brakes pads are unevenly worn or your rotors need resurfacing???

That's what I was thinking...

Automatic transmission, right?

Yes.

Don't the RS Yaris over there have ABS, with Brake assist , :iono:
In New Zealand they do , that would be your answer :thumbsup:

for US cars. when braking going down the hill, the brake does to brake on it's own too. it may be the ABS kicking in. i don't think it should be a problem for you.

I don't think ABS would kick in while going downhill. I do know that the Yaris simulates engine braking, but ABS should only kick in when slamming down the brakes, not when gliding to a slower speed. Besides, my issue happens even on flat roads just letting off the accelerator and gliding to a slower speed.

there's no way that the ABS is actuating automatically while going down a hill lol..

Yeah..

So I'm still thinking about if I should take it to the dealer to have it checked out. I'm just worried about how long it might take to investigate and fix if necessary.

supmet
05-11-2009, 02:20 PM
So I'm still thinking about if I should take it to the dealer to have it checked out. I'm just worried about how long it might take to investigate and fix if necessary.

If they'll check for free(even though they didn't for me when I was still under warranty) then go ahead, but I'd take it to Midas for brakes before the dealer. The dealer I took it to said it was normal for me to have to replace pads and rotors every 10,000 miles because I live in a hilly area. They charged me 50 bucks and I'm pretty sure they didn't even get the tires off. Only time I took my car to the dealership, and will definitely be the last.

I bought the R1 concepts rotors and carbotech pads from garm, and haven't had any brake problems since.

Loren
05-11-2009, 02:39 PM
My bet is that you're simply feeling the transmission downshift as you decelerate.

xtremesniper
05-11-2009, 03:49 PM
If they'll check for free(even though they didn't for me when I was still under warranty) then go ahead, but I'd take it to Midas for brakes before the dealer. The dealer I took it to said it was normal for me to have to replace pads and rotors every 10,000 miles because I live in a hilly area. They charged me 50 bucks and I'm pretty sure they didn't even get the tires off. Only time I took my car to the dealership, and will definitely be the last.

I bought the R1 concepts rotors and carbotech pads from garm, and haven't had any brake problems since.

Yeah it would be for free, I'm sure.. I've only owned it for a few weeks now.

My bet is that you're simply feeling the transmission downshift as you decelerate.

I was thinking about this, but I don't think that's it. Transmission downshift wouldn't feel like tapping the brake repeatedly, would it? When I drove the Echo it would speed up just a tad right as it downshifted, which I got used to. What's throwing me off is that it isn't happening all the time. From faster (normal) speeds to stopping, I don't feel it at all. The Yaris stops very smoothly and as I'd expect.

This particular feeling only comes about when I'm going slow, and I let go of the gas (for example, in anticipation of a red light or a speed bump) and then I realize the car is acting as if I'm tapping the brake over and over again, and the car slows down much faster than I expect, causing me to have to press the gas again even when in the Echo I wouldn't have had to.

nsmitchell
05-11-2009, 04:14 PM
How old is the car? Have you had tire work done? Have your wheels been taken off and put back on recently? If so, check your lug nut torque. 76ft/lbs is correct torque for Yaris lug nuts.

Myine was doing the exact same think. Kind of a pulsing feel like warped rotors. Turns out the guy that put my tires on over-torqued my lug nuts. Just getting them to correct torque fixed mine 95%. Now it's just a slight feeling when braking and it's getting better the more I drive it.

xtremesniper
05-11-2009, 04:16 PM
How old is the car? Have you had tire work done? Have your wheels been taken off and put back on recently? If so, check your lug nut torque. 76ft/lbs is correct torque for Yaris lug nuts.

Actually the car is very new. Only a few weeks old and had just under 50km on it when I picked it up.

nsmitchell
05-11-2009, 04:18 PM
I would still check the torque on them. Some mechanic may have over-torqued them unknowingly.

xtremesniper
05-11-2009, 04:22 PM
I would still check the torque on them. Some mechanic may have over-torqued them unknowingly.

I'm not quite sure of how to check that, but I know someone who owns a body shop. I guess I'll ask him when I get the chance. Thanks for the suggestion.

nsmitchell
05-11-2009, 04:25 PM
I'm not quite sure of how to check that, but I know someone who owns a body shop. I guess I'll ask him when I get the chance. Thanks for the suggestion.

You just need a torque-wrench and a 17mm or 19mm socket. You can borrow tools from Advance or Napa. You can check it in the parking lot. I'll bet they would do it for you if they're not busy.

YarisSedan
05-11-2009, 04:30 PM
Yeah as your engine downshifts it will feel like the car is going to lug slightly or in your case it will feel like the brakes had just became slightly more efficient. Since vehicl eis using transmission to slow down the speed of the car.

nsmitchell
05-11-2009, 04:37 PM
Toyota will definitely check your torque for you.

xtremesniper
05-12-2009, 01:18 AM
Thanks for the tips guys, I think I'll go in over the weekend to get it checked out.. I'll report back.

xtremesniper
05-20-2009, 01:28 PM
Okay so I wasn't able to go in just yet... But for a while I thought the issue went away but now it's definitely back. My friend drives an older Honda Civic sedan and she says her brakes are pretty bad (they squeal and everything), but I notice she has the same issue that I'm complaining about except for her it happens every times she brakes. But for me it's only in certain situations.

Still odd, and still going to go to the dealer soon. I'll report back again.

mojoyaris
06-03-2009, 10:43 PM
Any word on this yet? Was it a faulty oversensitive ABS sensor?????

xtremesniper
06-04-2009, 12:00 PM
Mmm nope, I went to the dealer and they took it for a spin and reported back that they couldn't find anything wrong with the car. They said that any behaviour it has is "normal for this type of car", but if it gets more prominent or worse, they told me to let them know.

To be honest, I think either I'm getting used to it now or it's wearing off as the car gets driven around more.