Brake pedal/ABS 'kicking' at low speed.

[1ZZ-FE]

Firstly, the ABS bulb in the dash does work as part of the start-up sequence.

Occasionally, light use of the brake pedal gives the sensation of the ABS activating and a reduction of braking effort. Whilst this is occurring, the ABS light doesn't flash, which seems odd to me!?

Lifting off the brake padal and reapplying remedies the problem. There might be a few minutes or hours of use before it occurs again. Very random. No fault codes present.

Any suggestions?!

Regards,
Jim

[Wabbitkilla]

What wheels, tyres, tyre pressures are you using?
What age are the tyres?
What brakes do you have fitted (disks and pads)?

[Jrichards20]

Have you recently changed tyres?

I am about to regret what I am going to admit buttt, I have just put on four budget tyres and only cruising around until August, and when I need to brake relatively light from a higher speed the same thing happens. I have just taken it to mean that i have terrible tyres and my rear tyres arent exactly the correct size. I would get all of that checked first as Wabbitkilla is asking.

[1ZZ-FE]

Toyo T1R all round. Drilled/Grooved discs front and standard rear. Standard pads all round. All new.

Regards,
Jim

[Wabbitkilla]

Everything is new?

Might just need a bit of time to bed in.
Tyre pessures?

[Jandaw]

Don't shout at me but...... Have you got you're grooved discs on the right way round? I know someone who hasn't and it's noticeable when braking.

Not me I hasten to add!

[mocelet]

I have had these symptoms on other cars when the castellated ring for the ABS sensor had split. I don't know if this is a possible problem on the MR2 though.

[1ZZ-FE]

Tyre pressures are to spec. Odd you should mention the direction of the discs - When I fitted them I initially fitted them the wrong way around, however, whilst fitting the other side a tiny piece of paper blew across my garage floor explaining the need for the correct direction! So I swapped them as described and have been fitted correctly.

A broken ABS ring is gonna be a bit of a pain to check but worth it. Damn.

Regards,
Jim

[wotugonado]

Do you get a bit of a whirring noise too ?

[1ZZ-FE]

Oddly, yes, when going round a left hander. I bought a wheel bearing, assuming it to be that.....could this be the ring?

[markyp]

I have had this fault on two cars...were the abs operates at slow speed braking, usually the last few yards when stopping at a junction.
The pulsed signal from one ABS sensor is weaker than the others at low speeds, This can be due to and rusty relector ring or build up of dirt between the ring and sensor.

The fronts wheels are the best place to look first....hopefully a careful clean will sort the fault.

[Wabbitkilla]

The trouble is the front ABS units are sealed inside the hub bearing units


So you can't really get in to clean them, but they have in a very limited number of cases been proven to go faulty.
The rear ones are open ring types, but it's very rare for one to fail.

[1ZZ-FE]

Thanks again for the info. There is a noise from the left rear. Coincidentally, the amount of brake dust on the left rear wheel is pretty bad compared to the others. Could be a good place to start?