Abs Concerns

[Cyker]

Hey all,

The ABS on my Yaris is starting to trouble me a bit. It's been acting a bit funny for while now but I didn't think it was a problem until today when I nearly rear-ended someone despite nearly standing on the brakes!

The symptom is that the ABS seems to be cutting in much earlier than I expect it to; In my old Yaris I didn't even know what the ABS felt like because it had never kicked in except for once or twice in the snow, but lately in this car I sometimes get that driving-over-gravel vibration feel under firm but still normal braking conditions.

I don't think it is the tyres as they are barely 3-month-old Premium Contact 5's, but one big coincidence in my mind is that I had this car serviced in Feb and had the brake fluid changed.

Would air in the brake fluid system cause this? Is there an easy trick to check?

[Sooty]

It sounds to as if the brakes have not been bled properly.

Unless I am mistaken, there is a balance valve in the system which controls the braking force to each wheel.

If this has been upset or off-set then you will get your symptoms.

Get the car back soonest and have the brakes sorted properly.

[Parts-King]

You appear to be saying that you had to stand on the brakes to stop in time? The ABS cutting in too soon would not stop the car from stopping, although people do consider the brakes are not working properly when the feel the judder in the pedal. Is it possible you were just too close to the car in front before you started to brake?

If the brakes had not been bled properly then the pedal would not feel right (it would be spongy or the pedal travel was too low)

If you feel the brakes are not working properly then it should be checked right away. Don't just assume having new brake fluid is the cause, there might be an altogether different problem that needs immediate attention

Kingo

[Cyker]

It's kinda hard to say; I've been driving Mk1 diesel Yarisususeses long enough to have built up a feel of what it's capable of and how it should behave and it just feels a bit off.

For instance, the Yaris is known to have quite a strong braking force, but lately it feels like I'm having to push down harder on the brakes to get the same kind of force and the ABS rumble (At least that's what I think it is!) seems to trip much more readily.

The most annoying thing is that most of the time it feels okay; I had a friend give it a go and he says it's fine and that I'm probably imagining it.

I can inconsistently get it to trip the 'rumble' early by braking gently at first then pushing it in harder to the stops and that's where the brakes don't feel as 'brakey' with the rumble. Normally I'd expect quite a sharp increase in braking force when I go from gentle braking to lots of braking but it feels like the early-ABS-ish feel is getting in the way or something??

If I just full-stomp on the brakes then I get the familiar tear-your-face-off braking force that I expect and no ABS rumble.

While I might get my travelling mechanic mate to look at it, I reckon if I take it to my local dealer without something more concrete than "It don't feel right", they'll just take it, say everything is okay and charge me for the privilege, probably assuming it's just driver paranoia!

You're right about not making assumptions of course; I was just throwing that out there as part of asking for suggestions and it's one of the things I don't know how to check. Brakes and tyres look okay, although I can't check the inboard side so it's possible there's something amiss there

This is a bit moot at the moment tho'; Gotta wait to get my car back before pursuing all that. Meanwhile I have to drive around in this crappy gutless Punto

Gotta get used to using the accelerator more when moving off and doing manoeuvres and not shifting up so early! I really miss that diesel torque!

[Parts-King]

I suppose it is entirely possible something is not working right with the EBD, that controls the "feel and effort" required to press the pedal, but that is not something to DIY check though

Good luck

Kingo

[Madasafish]

If the brake fluid has been changed or the brakes bled, has the cluch been bled?

The systems are the same and it is possible - indeed likely there is air - just a little in the clutch pipe.

It's easy to bleed . and it could just be the cause.

And it's easy to do...and costs little so in my opinion first port of call.

Then check the rear brake shoes are not sticking due to corrosion. That could give similar symptoms to those you describe.

I had strange braking pedal feelings for months. Checked the above : made a great deal of difference.

Then a front caliper could be sticking.

These are all basic and cheap checks.. but involve wheel removals in the latter two so not done at services.

[Cyker]

Okaaaay, my eagle-eyed brother (The one I gave my old Yaris to!) noticed this. Take a look at these and see what you think:

His Yaris:

My Yaris, passenger side:

My Yaris, driver side:

Specifically, look at the wear pattern on the brake discs. Clearly one of these is not as it should be 'eh!

This would explain the early ABS and lack of braking force!

Looks likes my ickle Yaris will be getting some new discs and pads in the near future! Surprised this wasn't picked up by the visual inspection...

[Madasafish]

That wear pattern suggest rusted slides/partially jammed caliper...

[Cyker]

Mah poor ickle Yaris finally went off for a replacement face!

I was dreading what hire car I was going to get as I was told it would most likely be a Punto (Boo!) or a Corsa (Hiss!) but to my surprise I got a Peugeot 107! :D

Haven't driven one for a while so it was a bit weird.

Handling and steering feel is much better than in the over-assisted Yaris steering. Nice weight on the steering gives much better feedback.

Suspension is much stiffer; Feels like the new Yaris in that regard - Much less roll in corners but shock absorption feels non-existent

Engine is a bit weird - Has great launch from a stand still but has absolutely no acceleration feel once you're moving! I am missing the feel of the diesel torque and the general torque abuse; It really doesn't like hills when full of people! Have to drop a lot of gears, but that isn't so bad. The engine is a bit dieselly at the low RPMs but actually gets quieter as the revs go up! (When I was getting used to the car, I once hit 40mph in 2nd gear thinking I was in 4th! ).

Only major gripe is the clutch; It's a 12 plate so I can't imagine the clutch is that worn, but it doesn't bite until you are almost letting go of it and the zone between initial contact and fully engaged is very small which made it a bit tricky to get used to. My Yarisusususesis clutch bites dead centre of the clutch travel and is much more progressive instead of being virtually on or off!

Don't remember the clutch being that nasty in the Aygo I drive years ago; Is that normal?!

Edit: Put all the linefeeds back in; Apparently the forum thinks they are tasty! Omnomnom

[MikeSh]

We have a diesel Yaris and an Aygo (petrol) and I feel your pain with the difference in 'pull'. The Yaris is just so much more confident.

As to speeds in gears on the Aygo/107. The other day I did an experiment in the Aygo (which is an MMT) by flooring it down the local dual carriageway. I got to 80 (indicated) and it was still in 3rd. It might have gone even further but there was a camera coming up, so I had to chicken out.

[Cyker]

Haha! If I tried that in my D4D I think the engine would fly out!

Must admit, I'm liking this 107 less the more I drive it; The clutch is still very annoying (If this was my car, I would have gotten it adjusted or changed!)

And today I could barely see where I was going due to the reflections from the top of the dash!

PArtly the problem is the windscreen is at too shallow an angle and the top of the dash is much deeper than in my Yaris.

The biggest problem is the stupid dotted pattern on the top of the dash - If it was just one uniform colour (LIKE BLACK OR GREY!) then it wouldn't be so bad, but with the silver dotted grid pattern it's like driving with raindrops on your windscreen that you can't get rid of! Gaaah!

The other thing that's weirding me out is the rear-view mirror - I swear it's slightly concave as everything looks bigger than they should. (Am I'm being tailgated by a giant stretched Ka?! )

Isn't the rear view mirror is supposed to a flat mirror?!

The side mirrors are ace tho' - A much larger view than the ones on my Yaris and they make reverse parking easier!

Want mah Yaris baaack!

[MikeSh]

Yep, dash reflections are bad in the Aygo too - plenty of posts about it in the Aygo forum.

Not had a problem with the mirror on mine. Maybe the Peugot is different - made for French people?

The Aygo/107/C1 is really pretty 5417 (for anyone who's had something even slightly better). I wish I'd spent my £££s on another 2nd hand Yaris now. If I did more miles/time in it I'd probably think about trading it in fact, but for what I do it's not worth the cost and hassle .... yet!

[Cyker]

Woo! Finally got mah Yaris back!

So good to be back in it now, with a nice clutch that you don't have to push 5 metres before something happens and the ability to accelerate!

Next just need to get my mechanic to have a free slot so he can do the brakes and sorted!

Have a few gripes with the repairs tho' so may lose it for a while again...:

- The lights are slightly out - The teardrop doesn't align with the corresponding bump in the bumper any more which suggests they have been pushed out slightly?

- There is a much larger gap (Almost a cm!) between the bonnet and the bumper when it's closed now. The whole area around the lights and between the bonnet and bumper has a significantly large panel gap than there should be!

- The drip guard that covers the gap between the front frame and the radiators and fan is missing completely (I don't suppose anyone knows what I mean and has a part number? Was trying to explain over the phone to my local Mr T but couldn't get them to understand... Even ToyoDIY doesn't seem to have it listed as a part! )

- The worst is that the bonnet is now extremely difficult to shut; Normally you can just lock it with a firm push but now I have to drop it from like, two feet up, otherwise it just bounces back into the 2nd latch and doesn't lock properly! I suspect this is mainly due to the misalignment...

Don't know if these are fixable things but surely they should have been able to bend back anything in the frame instead of just mounting everything on skewif!?

[Cyker]

Welp, shiny new EBC brakes and discs fitted.

Didn't make a bit of difference.

...

It made a MASSIVE difference! :D

I just came back from giving them a bit of a test (There is a network of resi streets near me perfect for this - Dead quiet and full of speed humps!) - I think there was a bit of a glaze on them as at first I didn't feel much difference, but I could feel them really biting down more and more as I braked for each hump; At the end run tried an emergency stop - went from 30mph to a dead stop without even getting near the speed hump, no ABS kicking in, front of the car diving down, seat belt locked up.

This more like the proper face-pulling Yaris braking I have come to expect!

Was looking at the old pads and it's pretty clear something was wrong; Two of them have noticeable grooves, maybe half a mm deep, curving along them and one has a noticeable 0.2-.4mm 'step' in the wear pattern. Not sure what the heck would cause that, unless the previous owner did something daft like changing the discs and not the pads?!

[Dougie150]

Think the bonnet gap and difficulty in closing can be sorted by following the advice given near the bottom of this thread (Dawesy gives the better answer after my comment).

http://www.toyotaownersclub.com/forums/lofiversion/index.php?t100908.html

[Cyker]

Ooh, good tip! I'll give that a go when I get a chance!

It's little tips like that that make this forum great!