Brakes / ABS problem

[Anonymous]

I've just looked at your photo's you posted originally  s:oops: :oops: s:oops:  

I had the same blueing or at least a band on the front disc's after a heavy session at Rockingham track - very fast with heavy braking, my brakes after this were not so good and in the end I changed the whole lot to EBC, the only thing I didn't need to change was the fluid, because I was running DOT 5.1 - what are you running? as it been changed, I know it's basic but certanily worth considering.

The other point is your comments about it getting worse, which indicates something is failing, if it was staying the same then you could put it down to say maybe the road conditions - so what could it be - well of the top of my head I would say, now I've seen your video of the roads, your shocks are probably on the way out, remember you have lowered your car on stock shocks, although Toyota do this it as been said a few times that the shocks can wear quicker - I could be wrong though  s:wink: :wink: s:wink:  

Looking at the state of your roads and the speed you drive I should imagine your shocks would only last about the third of the life of a standard car - this is not a criticism by the way just an observation  s:wink: :wink: s:wink:

Apart from the visual check it's difficult to tell if the shocks have gone or not, there is the obvious bounce test to see how quickly it settles, if there is a lot of wear then the car will bounce a few times before settling, but if it is only minor then it will be very difficult to pick up - you could always ask Toyota to check them.

Here in the UK the roads are a little better  s:shock: :shock: s:shock:  and the chances of putting the shocks under the same pressure are a lot less and there for we don't have so much of a problem.

I should imagine it's like driving the RAC rally on a weekly basis. s:shock: :shock: s:shock:  

Any way it's just a thought, I could be completely wrong but at least it's a start in an alternative direction.

Rob.

[Anonymous]

OK, tried the 'bounce test'. To be honest, the springs are so hard it's difficult to get them to move at all - let alone look for a bounce!

One thing I omitted to tell you, is that recently - in an effort to try to help the situation - I ordered and fitted LMCorse: chassis brace, plus upper and lower front ones.  Although it really improved the car's stiffness, it made no difference to my braking problem.


She booked in for her 3rd year service next week. I'll ask their advice on shocks. I'm still prepared to change the tyres though to something much softer. Any advice on which to choose would be welcome.

Nathan

[Anonymous]

Thanks guys, an update:

Went to local tyre fitter (I trust him, as he was the only person who I went to that immediately knew that the front were smaller than the rears!) and mentioned about the shocks. He tested them with a few good 'shoves' down on the bonnet and declared them perfect - a single bounce.

OK continued on to Toyota dealer for my 3rd year service:http://www.mr2roc.org/phpBB2/viewtopic.php?t=19539

During the service, discussed (again) with chief mechanic Yannis (he knows his stuff) about my braking problems. We noted - with all the wheels removed that the front discs are black and glazed looking! The rears less so - as expected, but the front nothing like I would normally expect a disc to look like (all shinny and polished). Yannis puts it down to the low mileage (km) that I do - about 10,00-km per year, but don't let that fool you. Our small island has no motorways. I could only dream of using 6th gear! Although I do less mileage than most, our twisty roads mean than I use my brakes much more than a member who sits on the motorway all day. Testament to this, when I first had braking problems (6 months ago) I immediately changed the front pads. Today, while inspected  the rears I was surprised to see that they only had about half their meat left (unusual as I expect the rears to hardly ware.)

Anyway. The discussion go to tyres. Yannis found a tyre density meter (never seen one before) - basically it looked like a tyre pressure guage - but had a small spike (needle) that you pushed into the tyre tread. The meter went from 0 to 100. My tyres registered 90 - that's hard. A nearby Auris 70, a toyota pickup 65 and a brand new Land Crusier (that was being 'blinged' with 10 grands worth of extras including all round DVD screens!) had 55.

OK, it seems that my Good Year F1's are way too hard. Before I change the discs, I will change the tyres, but need your help in choosing the softest tyre I can find for our rims...............

[Jaik]

While the Goodyears are quite hard tyres, they are grippy as long as they're not made in the far east, don't let a density reading suggest otherwise.

I think those brake discs are the bit to look at really. Not using them enough would just cause a build up of surface rust AFAIK. The blackness concerns me somewhat as I only know of that happening when the brakes are binding.

[loadswine]

I don't know the origin of your F1s nathan, but the ones on my other car are brilliant and have lots of grip, certainly better than the Bridgestone RE050s that were on it before, and a lot quieter. The Toyos are pretty soft, I think, but not sure what makes you have readily available.
Have you noticed any change in the grip the Goodyears give in the wet at all?
Did yannis make any comment on the black colouration on the disc?
Not sure why they should be glazing unless something is sticking.
I know you have higher ambient temperatures than here, but didn't think that would be responsible.
Mmm, perplexing!   s:? :? s:?

[Anonymous]

Strange about my F1's. To be honest, I notice very little difference in the wet compared to the dry! The handling of the car seems to be deteriorating too with slipping round corners all too offen. I wonder if the hot summer - into the 40s, we have recently had, masked the problem with the tyres as them were always warm. The current cooler winter days do not let the tyres to warm up, and hence show the problem.


OK, still on the hunt for new softer tyres and also think I will replace the discs.

Having used the search (hey I'm a good boy) have found that many members recommend these:

 m http://www.brakes4u.co.uk/products.asp?id=16383 m
(I would go for the Dimpled and Slotted Sport Discs - it is Christmas after all!)

Will the stock calipers and pads work with the above?

I supopose while I am changing the discs, I may as well add these:
 m http://www.brakes4u.co.uk/products.asp?id=18039 m

Anything else you recommend?

Nathan

[Jaik]

If the brakes are binding (especially the rear ones) that would affect the handling in corners too.

[Anonymous]

I don't think it is a binding issue. The braking is even (and braking firmly while not holding the steering wheel still results in a straight line.)

#Yesterday, while the car was up in the air and with the wheels on,  I gave each a spin. No drag or binding at all.

I am convinced it is a tyre issue.  Maybe my F1's are not the really thing (it is common in Greece to get fake items) and if I have actually got a cheap version rather than the much converted German ones?

I think though, while I am changing things, I will order new discs and brake lines. For the price of them (I don't think too excessive) and the peace of mind, I am sure they will be worth it. I've always loved the 2 for its handling and great stopping - the reason I choose it in the first place and will do anything to get it back to this.

Nathan

[loadswine]

With all those things, you should manage to nail the problem Nathan.
The tyres could be bogus , I guess, but they've been on a while and I would have thought you'd have had problems before with them.
Grooved discs are supposed to ward off glazing, so that may help, though you will probably get through a set of pads a little quicker than before.
They don't feel different, least mine don't.  s:) s:)

[Anonymous]

OK, have just ordered some Toyo Proxes. They should be here in 2 days.  (Cost 400 Euros - Ok it's Greece nad things are more expensive - but if it help cure my problems, then well worth it.) Still planning the disks upgrade and will order them very soon.

Nathan

[proeliator2001]

Only just spotted this thread (mainly because i'm a scarce visitor to these shores over the past 4 months - thanks work!).  I have the same problem, thankfully nothing like as bad, but on an 2004 model with under 30k miles I've had a fair few instances like you describe, normally in slightly damp conditions.  The fronts lock up stupidly easy and it massively increases my braking distance.  Scrared me a few times to the point where it would be nice  to have an emergency OFF button for the ABS   s:roll: :roll: s:roll:    

Seriously, when it's happened to me I'd have expected a 25 year old Fiesta with knackered rolling stock to pull up sharper and I'm quite convinced it's not the tyres overcoming grip, rather it's the ABS playing silly buggers.  As it's only happened a few times I'm not too fussed but it's interesting to see I'm not the only one.

I'm running standard RE040's and it's done it on worn and fairly new tyres but only from about 2 years old - is it the terrible twos? lol.  Oddly, it's not done it for a good few weeks (odd considering the slippy road surfaces) and as said, it's mildy moist (as TG would put it) conditions when it's the worst.

Good luck with the new tyres.

[ChrisGB]

Just another thought, have either of you tried pulling the ABS fuse and seeing if it is improved.

My ABS is occasionally fooled by a bump or ripple under braking (happened tonight on way home) but this also happens in other cars I own as well. The harder suspension of the MR2 does seem to make it worse once it triggers.

Chris

[Anonymous]

At last! Someone who know what I am going through! This braking problem is really ruining my enjoyment of the car. Yesterday I nearly crashed. 1km from home, it was wet and I was driving so slowly that I was trailing traffic (not easy on our roads). Slowly (40km) down a gentle hill and started braking for a sharp bend. ABS immediately on. I came off the peddle and gently re-applied. The same. I repeated this 4 or 5 times. I only just slowed enough for the bend. It was frightening.


Proeliator2001: interesting that you too have low mileage. That's the reason that Toyota gives me. They suggest slotted disks (drilled) as these keep the pads cleaner.

Chris: I didn't realise you could just remove a fuse to disable the ABS! Is it really that easy?
Chris: When hitting a small bump, when braking firmly for a corner, the ABS will usually trigger, but only once. The problem I have is not an occasional ABS, but full on, only stopping when I release the peddle.

[Anonymous]

Just checked the fuse box cover, but cannot identify which fuse is for the ABS

[kanujunkie]

Chris: I didn't realise you could just remove a fuse to disable the ABS! Is it really that easy?

be careful doing this, the ABS ECU  supplies the speed signal to the power steering and the guages

[ChrisGB]

Chris: I didn't realise you could just remove a fuse to disable the ABS! Is it really that easy?

be careful doing this, the ABS ECU  supplies the speed signal to the power steering and the guages

Sorry, should have made it clear that is should only be done as a test, remove fuse, drive in straight line over bumps and test brakes, re-insert fuse before driving on again.

When my car (cars) do it, there is only an occasional problem and it is most often when the damping has lost wheel control a little on surfaces that cause wheel patter. If you are seeing the problem regularly, I still think the number 1 suspect is the dampers. If you remove the ABS fuse and the car allows the wheel to lock or partially lock at the same braking forces, the ABS is working fine and you need to have a closer look at dampers.

Obviously, I have not driven the car, but from what you describe, it would be my train of investigation.

Chris

[Anonymous]

I see, thanks for the warning. Which fuse is it. Non of the fuse labels have any indication that they are ABS related.

[aaronjb]

Fuse box under the bonnet, middle fuse of the top three:

[kanujunkie]

is ABS2 fuse in there as well, i cant remember

[Anonymous]

ABS2 fuse? what does that mean, one for the front and one for the rears?

[aaronjb]

That's the only ABS fuse I could find in the BGB..

[kanujunkie]

look at the wiring diagrams, theres 2 fuses

[aaronjb]

Damn - I had to go scouring it again.. all your fault  s:P s:P

The second ABS fuse is in the same fuse box (front compartment) - it's the sixth fuse down.

Ah hell, have a diagram:


ABS1 is the middle fuse of the top three, ABS2 is the 40A fuse bottom right.


Looking at the wiring diagrams - pulling those two fuses will only stop the ABS actuating (you're pulling power from the ABS solenoid and ABS motor) - power to the ABS ECU itself comes from fuse ECU-IG, and I can't guarantee that isn't connected to other things as well as the ABS ECU.

[kanujunkie]

i'm going to have a sheer stab in the dark here and theorise that were going to find that the ABS1 fuse does control the ABS ECU and not the ECU-IG fuse. However i'm willing to bet that the speed signal for the guages is supplied by the power from the ECU-IG fuse. i'll give it a test and see

[aaronjb]

I'm not sure about that - look at the wiring diagrams and ABS1 & ABS2 only go to the switch side of (what is depicted as) a relay.. not into the main ECU connector.